Bring a large pot of water to a boil. Once boiling, add some salt, then boil pasta according to package directions.
Set out the milk, yogurt, and cheese so they can come to closer to room temperature.
Combine garlic powder, Italian seasoning, onion powder, salt and pepper. Season the chicken on both sides.
Heat a large, deep skillet over MED HIGH heat. Once hot, add 2 Tbsp of the butter, then when melted, add the chicken in a single layer. Cook, approximately 2-3 minutes per side, until cooked through. Set chicken aside on a plate, but don't clean out the skillet.
To the same skillet, add remaining 2 Tbsp of butter and 1 Tbsp olive oil and melt over MED heat. Once melted, add flour, whisking together until combined.
Cook 1-2 minutes, whisking often, then add the milk and Greek yogurt. Whisk together until smooth, then reduce heat to LOW and simmer.
Simmer several minutes until sauce thickens enough to at least coat the back of a spoon.
Once thickened, remove from the heat and stir in the mozzarella cheese until melted and combined.
Add drained pasta and cooked chicken to the skillet and stir until combined and heated through.
Garnish with some minced fresh parsley if desired. Taste and add a sprinkle of salt and pepper if desired.