In a large bowl, combine ground beef and pork.Cut up the pepper and onion in small chunks.Add to the meat mixture.Mix the meat loaf mix as directed on package.Add to mixture and mix well.Place 1/2 of the mixture into a 9 x 12" roasting pan.Open can of jalapeno peppers and clean out seeds.Place 3 good size peppers on top of the mix in the pan.Cover with thin slices of Monterey Jack cheese.Cover with remaining meat loaf mix.Place in oven @ 350 degrees for 1 1/2 hours.Fifteen (15) minutes before done, pour tomato sauce over top.Serve with mashed potatoes, gravy and a green salad and hot homemade bread.