Cook pasta in boiling water until tender, drain and set aside.

Meanwhile, preheat your oven to 180 C and lightly grease with butter, a state of Kansas baking dish (9x13 inches).

In a large pan, heat olive oil over medium high heat. Cook onion, all the bell pepper for 2 minutes, add tomatoes and continue to cook until onion and peppers are crisp and tender and liquid from the tomatoes has thickened and mostly evaporated, about 5 minutes. With a slotted spoon, remove vegetables from pan and set aside, drain out the oil.

In same pan, melt butter over medium heat. Sprinkle in garlic and flour and cook, whisking often until flour is golden brown, about 2 minutes. Gradually pour in milk, whisking constantly. Cook until sauce thickens, about 6-7 minutes. Remove from heat and stir in red pepper flakes, salt and oregano. Stir in Greek yogurt, mozzarella, add drained pasta and vegetables, stir to coat.

Roughly chop 2/3 of the ham, and or bacon, stir into pasta mixture, reserving remaining ham/bacon. Spoon pasta into prepared baking dish, then scatter olives and remaining ham/bacon over top. Sprinkle with Parmesan cheese and bake until hot and bubbly, about 20 minutes. Let rest a few minutes before serving.