Beef & Cheese Stuffed Manicotti

I can't imagine how this recipe hasn't gotten onto my blog earlier. Probably because it's easy to alter and adjust the stuffing with various ingredients, and I often make it without following any exact recipe. 

Ingredients
1 onion, diced
1 - 2 T olive oil
1 - 1½ lbs hamburger
s & p
½ green pepper, diced
½ red pepper, diced
3 - 5 garlic cloves, minced
32 oz ricotta cheese
8 oz grated parmesan (or cheddar, or other firm cheese)
8 oz sour cream
2 T Italian herbs - store bought mix, or your own favorites
64 oz spaghetti sauce
8-12 oz shredded mozzarella

Directions
Heat oil in skillet; add onions and cook until translucent. Add hamburger, cook until thoroughly browned. Salt and pepper to taste. (I often use garlic salt or onion salt for added flavor, and usually choose crushed red pepper flakes instead of black pepper.) Add garlic and diced peppers; heat through until very fragrant. Set aside to cool slightly.

In a large bowl, combine ricotta, grated parmesan, sour cream and herbs.  Once beef and vegetables are cooled -- just enough so as not to melt cheeses -- combine them with ricotta mixture.

Pour a layer of spaghetti sauce on the bottom of a casserole dish. Stuff uncooked manicotti noodles, arranging them in the baking dish. Pour more spaghetti sauce over noodles; a second layer of stuffed manicotti may be added, or use a second casserole dish. Top with another layer of spaghetti sauce; sprinkle shredded mozzarella over tops.

Bake 1 hour at 325°F.
Casserole can also be frozen, and baked later.