Preheat the oven to 350 degrees F (175 degrees C). Line a baking pan with parchment paper.
Melt butter in a saucepan over medium heat and whisk in flour until smooth. Whisk in milk. Add 1/2 teaspoon garlic powder and 1 1/4 cup Parmesan cheese. Stir Alfredo sauce until melted and smooth, about 5 minutes. Set aside.
Combine remaining garlic powder and Italian seasoning in a bowl. Rub mixture evenly on both sides of chicken breast.
Heat a grill pan over medium-high heat. Add chicken breast and grill for 3 minutes per side. Remove from pan and allow to rest for 5 minutes. Slice into thin strips.
Cut pizza dough in half and shape each into a heart. Place dough on the prepared baking sheet and pierce all over using a fork.
Bake untopped dough in the preheated oven for 5 minutes. Remove from oven and spread with Alfredo sauce. Top with sliced chicken strips, chopped spinach, remaining Parmesan cheese, and mozzarella cheese.