Preheat your oven to 400ºF and line a 13x18-inch sheet pan with parchment paper.
Put the onion, bell peppers, celery, garlic, jalapenos, tomatoes, 2 tablespoons olive oil, salt, and pepper in a large bowl and toss until the vegetables are evenly coated.
Spread the vegetables in a single layer on your prepared baking sheet. Add the slices of Andouille sausage.
Roast for 15 to 20 minutes, or until the vegetables are tender and start to brown.
Meanwhile, toss the shrimp with the Cajun seasoning and cook the linguine according to the package directions.
Place the shrimp on the vegetable mixture, and top with half the lemon wedges.
Roast for 5 to 8 minutes more, or until the shrimp is no longer pink.
Toss the mixture with the cooked linguine, and garnish with the green onions and parsley. Serve the pasta with the remaining fresh lemon wedges on the side.
Recipe by Go Dairy Free at https://www.godairyfree.org/recipes/spicy-jambalaya-pasta