Bring a large pot of salted water to a rolling boil. Add pasta and cook for 8–10 minutes. In the final minute, add frozen peas. Drain pasta and peas together.

In a skillet over medium heat, add sliced kielbasa. Sauté for 5–7 minutes until browned. Remove kielbasa and keep warm.

In the same skillet, add red pepper strips and sauté for 3–4 minutes until tender. Remove and keep warm with kielbasa.

Melt butter in a saucepan over low heat. Stir in cream cheese and parmesan until smooth. Gradually add cheddar and Monterey Jack cheese, stirring in milk for desired consistency.

Return pasta and peas to the skillet, add kielbasa and red peppers. Pour cheese sauce over the mixture, stirring to coat evenly. Warm through and serve immediately.