Cook smoked sausage in large skillet over medium heat until slices begin to brown. Drain fat and place in a large bowl.
Cook cabbage and onions in oil in the same skillet, covered, until soft. Add Sriracha sauce, salt and pepper, and add to bowl with smoked sausage. Cook noodles in chicken broth, drain, reserving about 2 c. of the broth. Add to the bowl with the other ingredients and toss everything with the cheese. Add reserved broth as needed to desired moistness; err slightly on the side of wet.
Pour into large, greased baking pan and cover. Bake at 350 degrees F for 30 minutes and remove cover. Bake 15 minutes longer, or until edges begin to brown.
This casserole was a big hit at a small luncheon today. Two people asked for the recipe. I put it together yesterday, and baked it at the church today.