Tortellini w/ Mushrooms in Lemon-Basil Parmesan Sauce

I typed this recipe up in June, maybe July? I guess it got lost in my many other things I have yet to get around to making. Well I wish I had given it a try sooner because it is very tasty and an easy one to make. It's creamy, but not over-whelming where the noodles get lost in the sauce. The lemon in the sauce is a great compliment with the basil and the mushrooms. Finally, the added topping of fresh mozzarella, for that extra ooey-gooey goodness we all love.

Tortellini w/ Mushrooms in Lemon-Basil Parmesan Sauce

Ingredients
20oz pkg refrigerated tortellini (I used Buitoni Herbed Chicken)
1-1/2 tbsp unsalted butter
2 tbsp flour
1 C milk
1/2 C grated Parmesan
3 tbsp fresh lemon juice
1 tsp lemon zest
2 tbsp olive oil
1/2 onion, chopped
10oz sliced mushrooms
3 cloves minced garlic
about 3/4 of a well-drained 10oz can diced tomatoes
about 1/3 C chopped fresh basil
fresh mozzarella, thinly sliced
1/2 tsp garlic powder

Preheat oven to 350º.

In a large pot, cook tortellini according to directions on package. Meanwhile in a small saucepan, melt butter over medium heat, add in flour and stir until light brown and smooth. Slowly whisk in milk and stir frequently until thickened (thick enough to coat the back of a wooden spoon). Stir in Parmesan, zest, and basil. Remove from heat and set aside.

In a saute pan, heat the olive oil over medium-high heat. Add the onion and mushrooms, cook until tender, and mushrooms begin to caramelize. Add the garlic, cook about 1 min, then stir in the lemon juice and and diced tomatoes.

Drain the tortellini. Combine noodles with mushroom mixture and Parmesan sauce. Transfer into a 13x9" baking dish, top with slices of fresh mozzarella. Sprinkle the top with garlic powder. Bake about 20-25 min.