Preheat the oven to 425°F. Arrange cooked tortellini in the bottom of a 9×13-inch baking dish. Set aside.
In a small bowl, mix olive oil, Italian seasoning, salt, and pepper. Coat chicken breasts in the mixture.
Grill chicken over medium-high heat (425–450°F) for 7–8 minutes per side or until internal temperature reaches 165°F. Allow to rest, then slice.
In a saucepan, melt butter over medium heat. Add minced garlic and garlic powder, stirring until fragrant. Sprinkle in flour and whisk until smooth. Gradually add milk and cream, whisking continuously. Bring to a boil, then simmer until thickened. Remove from heat and stir in grated parmesan cheese.
Pour Alfredo sauce evenly over the tortellini. In a bowl, mix bread crumbs, asiago cheese, and olive oil; sprinkle over the sauce.
Place in the oven for 15 minutes or until bubbly and lightly browned.
Top with sliced grilled chicken and garnish with fresh parsley.