Shake Shack's new pizza burger comes sandwiched between slices of focaccia

• Shake Shack and New York City pizzeria Mama's TOO! have joined forces to create a hybrid burger.
• The Mama's Too! burger includes a double cheeseburger with Stracciatella cheese, spicy 'Nduja tomato sauce, bitter greens, and crispy garlic.
• Mama's TOO! homemade focaccia bread — baked with Parmesan, mozzarella, and rosemary — holds everything together.
• Shake Shack and Mama's TOO! focaccia burger costs $10.49 and will be available to New Yorkers on Thursday.

What happens when you combine a burger with a pizza? Shake Shack decided to find out.

Shake Shack has joined forces with New York City pizzeria Mama's TOO! to release a brand new focaccia burger.

The Mama's TOO! burger — as it's been named — features a double cheeseburger with Stracciatella cheese, spicy 'Nduja tomato sauce, bitter greens, and crispy garlic.

Holding everything together is the pizzeria's homemade focaccia bread, which is baked with Parmesan, mozzarella, and rosemary, a Shake Shack spokesman told Insider.

Mark Roasti, Shake Shack's culinary director, wanted to strike "that perfect balance" between burgers and pizza, he said in a statement sent to Insider.

"We wanted to create something really fun, and highlight the best from both worlds," he added.

Mama's TOO! owner Frank Tuttolomondo said Shack Shack has always been a source of inspiration at his Upper East Side pizzeria.

"We both love to highlight the most craveable flavors and textures throughout our menu," he said. "This is a burger unlike any that you've had."

Shake Shack and Mama's TOO! focaccia burger costs $10.49 and will be available to New Yorkers on Thursday at Shake Shack's Madison Square Park location.

Diners must order the burger for pickup ahead of time through Shake Shack's app or its website.

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