Garlicky Shrimp and Feta Cheese Stuffed Shells

Heat oven to 400 degrees F. Cook jumbo shells according to package directions. Drain and rinse under cold water to cool. Spread 1 3/4 cups marinara sauce on the bottom of a large broiler-proof baking dish. In a large skillet, heat olive oil, garlic, lemon zest, and crushed red pepper flakes over medium heat until the garlic begins to brown, about 2 minutes. Add fresh lemon juice, capers, and roasted red pepper and toss to combine. Remove from the heat and stir in remaining 1/2 cup marinara sauce. Toss with shrimp to coat. Fold in baby spinach, fresh basil, 1/4 cup crumbled feta, salt, and pepper. Spoon the mixture into the shells (about 1/4 cup each) and place on top of the sauce. Sprinkle with 1/4 cup crumbled feta, cover with foil, and bake until the shells are heated through, 12 to 15 minutes. Heat broiler. Uncover, and broil until the cheese begins to brown, 2 to 3 minutes.