Heat a large frying pan to med-high heat. Add the olive oil and throw in the beef, garlic powder, salt and pepper, onion, garlic, and mushrooms. Cook till the beef is cooked through and the mushrooms are nicely browned. Make sure to break up the beef as it cooks.
Add the tomatoes, chopped and crushed, the salt and the juice from the jalapenos and as many jalapenos as you like. I add 3/4 of the jar and it's got some good kick but not too spicy. Cook down till the tomatoes are like a sauce.
While the sauce cooks, heat a pot of water on the stove on high. When it boils, throw the pasta in. Cook the pasta till el dente, or till it still has some bite to it, but its almost cooked through.
Mix it with the beef sauce, pour it in a casserole dish and sprinkle the cheese on top.
Bake at 400 till the cheese is bubbling and browned. About 20 mins or so, but check it after 15 in case.
Serve right away!
After you add the tomatoes and crushed tomatoes, add the juice of the jarred jalapeños and cover. Let simmer for 5 mins at least.