I'm a mom of 10 who's shopped at Costco for 20 years. Here are 20 things I always buy in bulk.

• The bulk grocery items available at Costco are perfect for feeding my family of 12.
• The store also sells household essentials, so we never run out of things like toilet paper.

My husband and I have 10 kids ranging in age from a toddler to 20-something. As you can imagine, it takes a lot of food to feed all 12 of us.

Even though my nearest Costco is almost an hour's drive from my home, the store's great prices and huge selection of items make it worthwhile for me to shop there. Each month, I head to the store with a couple of kids, and we fill up a cart with the food we need for the coming days.

Though my exact selection varies from month to month, here are 20 items I regularly buy in bulk at Costco.

Note: Prices are based on one Costco in Spokane, Washington, and they might differ from location to location.

This plastic wrap lasts forever — I only have to buy it twice a year

Once a week, we have a leftover lunch, and this plastic wrap from Costco makes that meal simple.

Whenever we have extra food during the week, we put it on a plate or in a container and cover it tightly with this wrap. The cutter works well, so my older children can even help with the task. On leftover days, I pull everything out from the fridge, and the kids heat up what they want.

Plastic wrap is one of those things you don't want to run out of, and buying little rolls can really add up, so this is a good deal.

Costco sells packs of two rolls of plastic wrap, each with 750 feet, for $11.29.

Popcorn is a cheap, tasty snack that everyone in my family enjoys

My kids always seem to be ready for a snack, and popcorn is a family favorite, so I pop up two large batches several times a week.

I add a bit of oil to a pan and cover the bottom with a single layer of kernels. Then I put the lid on and shake over medium heat until the popping slows. A little melted butter and popcorn salt finish the preparation, and the kids are ready to dig in.

This 8-pound container of kernels lasts my family about a month. And at $11.49, it makes for a frugal snacking option.

Rice goes with almost anything, so it's on our meal plan several times a month

Rice is so versatile and inexpensive, so my family eats it frequently. Hamburger rice bowls, egg fried rice, Spanish rice, and chicken rice casserole are go-tos on my rotational meal plan.

Jasmine rice cooks up quickly in the Instant Pot, which is my favorite way to prepare it. For my large family, I use 4 cups of dry rice for each meal.

This 25-pound bag of jasmine rice costs $21.99 at Costco.

10 kids go through a lot of milk

Whether it's milk for drinking, milk for baking, or milk for cereal, my family goes through a lot of the stuff.

Luckily the low prices at Costco make it the perfect place to stock up.

A two-pack of whole-milk gallons goes for $5.59.

A dollop of sour cream makes tacos, nachos, and baked potatoes better

Sour cream is the perfect topping for many delicious meals. It's also a special ingredient for fluffy pancakes, biscuits, and other baked goods.

This 3-pound container of sour cream lasts for quite a few meals, and I appreciate its simple ingredient list.

Each container costs $3.99.

I never want to run out of toilet paper in my house

Because I homeschool my crew, nearly my whole family is home all day long. With that many people using the bathroom, toilet paper goes quickly around here, so I always buy it in bulk to make sure we have some on hand.

Costco is my favorite place to purchase this necessary item. The pack of 30 rolls lasts us just about a month, so I grab a pack each time I shop there.

Each package of 30 rolls costs $14.99.

This pork tenderloin cooks up into a tasty meal

I like preparing a special meal for my family to eat after church each Sunday.

I can make this pork tenderloin in my Crock-Pot or Instant Pot, so it's one of my go-to options. It's delicious when paired with mashed potatoes or a noodle dish.

For $3.49 per pound, you get four delicious tenderloins.

Butter makes everything taste better

Each time I shop at Costco, I buy several packs of salted butter.

I keep one of the four-packs in the fridge and toss the rest into the freezer so I always have some on hand — and don't have to buy it at a higher price from my local store between Costco runs.

We use this butter for baked goods, potatoes, noodles, popcorn, and more.

Each pack contains four 1-pound boxes of butter and costs $8.49.

Sliced ham is good for more than just sandwiches

Ham sandwiches make a quick lunch. But that's not the only thing I use this ham for.

I dice it up and add it to egg-fried rice, use it in quesadillas and scrambled eggs, and sprinkle it on top of baked potatoes.

Since it's good for so many quick meals, I make sure to always have a pack or two on hand.

Each package comes with two bags of ham and costs $9.79.

This massive bag of brown sugar makes a lot of homemade cookies

Many recipes require brown sugar, so I buy this 7-pound bag about every other month.

I tried buying the even larger package but found it got hard before I reached the bottom, so this medium-size bag works perfectly for my family.

Each bag costs $5.99, which works out to about $0.86 per pound.

These hamburger patties help get dinner on the table in a hurry

Hamburgers and french fries are a family favorite, especially when we're having company for dinner.

Each bag comes with 18 pre-formed patties, so it's the perfect size for one family meal with a few guests.

Plus these patties cook up quickly, which means I can spend more time enjoying my family and less time in the kitchen.

Each bag costs $16.99.

Greens add a healthy dose of vitamins to our smoothies

Don't tell my kids, but there's a super-secret ingredient in the smoothies they happily chug down. These large bags of greens make it simple to add an extra helping of vegetables to my family's diet.

I also mix these greens with lettuce to make a salad. But these won't last that long in the fridge, so I only buy a couple of bags each trip. If I purchase too many, the leaves turn slimy before I can use them.

Each bag of greens costs $4.99.

Chocolate is a necessity, and a handful of these chips can satisfy a sweet tooth

My family really likes chocolate, so I always have one of these large bags of chocolate chips in the pantry.

I dole them out as treats for solving math problems, completing chores, and other tasks.

They're also tasty in chocolate-chip cookies, brownies, and other treats, and I've mixed them with popcorn, nuts, and raisins to make a quick trail mix for hikes or car trips.

Each bag is over 4 pounds and costs $9.99.

I always make sure to have lemon juice in my fridge, and these bottles actually last

Little bottles of lemon juice from most grocery stores don't last too long around my house. That's why I buy this pack at Costco instead.

There's plenty of juice in these 48-ounce bottles for making lemonade and lemon bars.

Each pack contains two bottles and costs $5.59.

Chicken thighs are so juicy and flavorful, and they're more affordable than breasts

Chicken thighs have a lot going for them. They're typically less expensive than chicken breasts and pack a lot of flavor, so I always buy a couple of bags to keep in the freezer.

I use them in recipes that call for chicken breasts — like chicken teriyaki, stir-fry, and oven-baked chicken dishes — to help keep costs down. They're also perfect for cooking in bulk and shredding for tacos and casseroles.

The packages have over 6 pounds of chicken and cost $11.99.

A bit of whipped cream on top of these frozen blueberries makes a great snack

Blueberries are so tasty, but they aren't in season for long. These Costco bags of frozen berries make it possible to enjoy them all year.

I use these for pancakes, muffins, and smoothies. I also put them into bowls and add whipped cream on top for a quick dessert or snack. My kids love eating them frozen, but I prefer to let my dish sit for a bit so they're a little softer.

Each 5-pound bag of blueberries costs $8.29.

Buying shredded cheese saves me a lot of time

This is my favorite blend from Costco, the cheddar and Monterey Jack go well with so many different recipes.

I add some to a tortilla and pop it in the microwave for a quick kid-friendly quesadilla. It also works perfectly for sprinkling on top of toast, scrambled eggs, making tacos, or any other dish that needs a bit of cheese.

Each package costs $13.69 and contains two bags, for a total of 5 pounds of shredded cheese.

We use bacon for breakfasts, lunches, and dinners

It takes a lot of bacon to feed a dozen people. That's why I always buy it at Costco.

I usually bake the bacon instead of frying it to cut down on the greasy splatter. Once it's cooked, it's a favorite for breakfast, but I also add slices to hamburgers and dice it up to use on top of baked potatoes.

Each package contains four 1-pound packs of bacon and costs $15.49.

I keep this olive oil near the stove so it's always there when I need it

Extra-virgin olive oil is my go-to for salad dressing and sauces. But I don't like the flavor it imparts on food when cooking. So for pan-frying, popcorn, and general cooking, I grab this more neutral-tasting olive oil instead.

Each large bottle lasts quite a while, but when I open the second one, I make a point to pick it up again the next time I go to Costco — that way I always have some ready in the pantry.

The two 2-quart bottles cost $19.89.

These large loaves of bread make quite a few sandwiches

If I buy regular loaves of bread, it'll take a couple to make sandwiches for the whole family. But with these large loaves, I only need one to feed everyone.

The kids like that there aren't any nuts or seeds, and I like that it's 100% whole wheat. The bread makes great sandwiches — grilled cheese is a family favorite — and toast.

Each loaf is 32 ounces, and the package comes with two for $4.99.

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