Pot Roast Penne

I have made this with leftover roast, but this time I made the roast especially for this dish. I just cooked it in the slow cooker with some tomato soup, water, garlic powder and basil for several hours. Then I cut it up to use in the recipe. I used the new mini penne from Barilla and I prefer it to the larger pasta in this dish. My brother-in-law's brother Mike was staying with us this weekend and helped me cook so this went together pretty fast.
Pot Roast Penne

1 tsp. salt

1 pound penne pasta

1 Tbsp. olive oil

2 garlic cloves, minced

1 small red onion, thinly sliced

2 tsp. herb-flavored mustard such as rosemary or tarragon

1 cup beef broth

1 cup leftover beef gravy

1/2 tsp. freshly ground pepper

2 cups cooked, shredded beef pot roast

1 cup cooked vegetables such as carrots or peas

Grated Parmesan cheese, optional

Bring a large saucepan of water and 1/2 tsp. of the salt to a boil over high heat. Add pasta. Cook until tender, but still firm to bite. Drain. Meanwhile, heat olive oil over high heat in a large skillet. Add garlic and onion. Reduce heat to medium. Cook, stirring until onion softens, about 3 minutes. Whisk in mustard until smooth. Add broth. Cook, stirring often until reduced by half, about 5 minutes. Stir in beef gravy, remaining salt and pepper. Cook until heated through, about 3 minutes. Stir in beef, heat through, about 2 minutes. Stir in vegetables. Heat through, about 1 minute. Return pasta to large saucepan. Pour in beef mixture. Toss to coat. Top with Parmesan cheese, if desired.