Wash and dry all produce. Adjust rack to middle position and preheat oven to 450 degrees. Core, seed, and thinly slice bell peppers. Halve, peel, and thinly slice onion. Toss bell peppers and onion with salt, pepper, and a drizzle of olive oil on a baking sheet. Roast in oven until tender, about 25 minutes.

Toss green beans on another baking sheet with a drizzle of olive oil and a pinch of salt and pepper. Roast in oven until tender and lightly crisped, 10-15 minutes. Meanwhile, heat a drizzle of olive oil in a large pan over high heat. Season beef with salt, pepper, and Italian seasoning.

Add half the beef to pan and cook, tossing occasionally, until browned, 2-4 minutes. Remove from pan and set aside, then repeat with remaining beef. Once bell peppers and onion are done roasting, toss with beef on same baking sheet.

Split baguettes in half lengthwise, stopping before you cut all the way through. Toast in oven until lightly golden, about 5 minutes. TIP: Place the baguettes on the same sheet as the green beans, if there’s room.

Wash out pan used for beef and return to stove over medium heat. Add 2 TBSP butter and let melt, then whisk in flour. Cook, stirring frequently, until pasty and lightly toasted, about 1 minute. Slowly whisk in milk, adding a little at a time. Bring to a simmer and let bubble, whisking, until thickened, about 1 minute. Remove from heat and add cheddar, stirring to melt.

Spread a little cheese sauce inside baguettes (save some for dipping), then fill with bell peppers, onion, and beef. Sprinkle with hot sauce (to taste) for the adults. Divide between plates and serve with green beans on the side. Divide remaining cheese sauce between small bowls for dipping.