Put sausage links in large skillet with about 1/2 cup of water, bring to a boil over high heat. Cook for about 5 minutes, allowing sausage to firm up.
Meanwhile, chop onion into large 1/2" pieces, cut red pepper into 1" chunks, cut potatoes (leaving skin on) into 1 1/2" dice, and cut jalapeno peppers into strips. Combine all vegetables in large bowl, drizzle with olive oil. Salt and pepper liberally, and toss all to coat.
Remove sausage from skillet and cut each link into 3 pieces. Add to bowl with vegetables and toss well.
Spread mixture evenly onto sheet pan sprayed with cooking spray. Bake, uncovered, for about 20 minutes. Remove pan from oven, and stir well. Return pan to oven and continue cooking for about 10 more minutes, or until potatoes are tender, and all ingredients are browned.