Baked Pesto Pasta

My friend had a pesto pasta dish at a restaurant that she swore was almost the best pasta she had ever eaten.  Pesto, creamy sauce, chicken, and pancetta.  Pancetta isn't really my favorite thing and I find that it is very expensive in my area, but the rest I could do easily enough.

Makes 4-6 servings

3 cups penne
1 tablespoon olive oil
1 clove garlic
3 oz spinach, chopped
6 oz cooked chicken, chopped
Dash salt
1/4 teaspoon garlic salt
1/4 cup Pesto
3 tablespoons flour
2 cups milk (I used 2%)
1/2 cup Parmesan cheese
1/8 teaspoon salt
1/4 teaspoon garlic salt
1 cup shredded mozzarella cheese

1. Cook penne in salted water according to package directions, undercooking by a couple of minutes.  Drain pasta and pour into a greased 9x13 inch pan.
2. In a small skillet, saute garlic in olive oil.  Add spinach and saute until wilted.  Stir in dash salt and 1/4 teaspoon garlic salt. Remove from heat.
3. Mix sauteed garlic and spinach with pasta.  Add pesto and chicken; stir well.  Set aside.
4. Whisk flour with milk.  In a medium saucepan, heat sauce over medium heat while stirring constantly.  Cook sauce until bubbly and thick.  Remove from heat and stir in Parmesan cheese, 1/8 teaspoon salt, and 1/4 teaspoon garlic salt.  Stir until cheese is melted.
4. Pour sauce over evenly over pasta; do NOT mix.  Top sauce with mozzarella cheese.
5. Bake pasta in a 350 degree oven for 30-45 minutes or until top is golden brown.  Serve hot.