Step 1
Set an oven rack to the top position and preheat to 400 degrees F (200 degrees C). Line a baking pan with aluminum foil. Coat a 9x13-inch baking dish with cooking spray.
Step 2
Bring a large pot of lightly salted water to a boil. Cook elbow macaroni in the boiling water stirring occasionally until tender yet firm to the bite about 8 minutes. Drain macaroni reserving 2 1/2 cups pasta water. Pour macaroni back into the pot.
Step 3
While the macaroni is cooking place prosciutto on the prepared baking pan.
Step 4
Cook prosciutto on the top rack of the preheated oven until dry and crispy but not burnt 6 to 8 minutes. Remove from the oven and chop roughly. Lower the oven to 350 degrees F (175 degrees C) and lower the rack to the middle position.
Step 5
Melt butter in a saucepan over medium heat. Add flour and whisk for 1 minute. Add garlic powder cumin red pepper flakes and pepper; cook for 1 minute more. Whisk in Greek yogurt and cook until heated through and bubbling 2 to 3 minutes. Whisk in 1 1/2 cups of the reserved pasta water; cook for 2 to 3 minutes.
Step 6
Add cream cheese and stir until melted. Add a generous 1/4 cup each of Gruyere and Cheddar cheeses stirring until thoroughly melted; repeat until all cheese had been added and sauce is thick. Stir in as much of the remaining pasta water as necessary to reach desired consistency.
Step 7
Stir spinach into the cooked macaroni. Add cheese sauce; stir until combined and macaroni is coated. Pour into the prepared baking pan and sprinkle prosciutto over top.
Step 8
Bake in the preheated oven until edges are bubbling slightly 15 to 20 minutes.