Preheat oven to 400.
Cut the top off the head of garlic so it still remains in tact. Drizzle 1 teaspoon or so olive oil over top, wrap in foil and place in the oven for 35-40 minutes. Remove and cool, then squeeze out the garlic, it should be like a paste.
1 head of garlic
Combine yogurt and 1 1/2 cups wheat flour in a stand mixer with the dough attachment and stir until combined well (alternatively, you can stir by hand).
1 cup plain nonfat Greek yogurt, 1 1/2 cups whole wheat flour
Roll dough into a circle about 1/4 inch thick. Prick with fork and bake on a pizza pan at 400° for 10 minutes.
While the crust is baking, over medium heat, whisk 4 tbsp olive oil and 4 tbsp flour until it bubbles. Add warmed milk a little at a time, constantly whisking to blend. It will thicken after each addition. When all milk is added, add roasted garlic, salt, pepper and nutmeg, continue to whisk until the mixture is well blended and thickens up, about 5 minutes.
4 tablespoons +1 teaspoon olive oil, 4 tbsp all purpose unbleached flour, 2 cups milk, 1 tsp salt, 1/2 tsp pepper, 1/2 tsp nutmeg
Spread 1 cup white sauce over pizza crust. Add chicken, spinach, and cheese. Bake for 10 minutes, serve immediately.
1 1/2 cup cooked chicken, 1 1/2 cups spinach, 2 cups mozzarella