heat oil in large skillet. While this heats, coarsely chop bell peppers and onion. Add these to the hot pan, cook on medium high until tender then add seasoned flour and pepper. Mix well, add milk all at once. Cook, stirring often, till it begins to thicken up a little. Add the grated cheese and asparagus, stir until cheese is melted. Add lemon juice and crumbled salmon, mix in with reserved pasta.