Preheat oven 350. In large pot of boiling salted water, cook pasta. Drain well and place pasta in a bowl. Drizzle with olive oil and toss to keep from sticking.
In deep skillet, heat 3 T. olive oil. Add onion and bell pepper and cook until soft.
Add beef and cumin and cook until meat is browned and any liquid has evaporated.
Add flour and cook until no floury taste remains.
Stir in tomatoes and stock and simmer until thickened. Scraping up and browned bits from bottom of pan.
Remove from heat and stir in pasta, cream, parsley and 1 c. of cheese. Mix well. Season to taste.
Transfer to large baking dish that is at least 2” deep.
Sprinkle with remaining cheese and panko on top.
Bake 15 minutes, until bubbly and cheese is melted.
Let stand 5 minutes before serving. Garnish with chopped green onions.
Recipe by Geaux Ask Alice! at https://geauxaskalice.com/mac-cheese-casserole/