Preheat oven to 400°F degrees.
Cut French baguette lengthwise in half.
Mix minced garlic with softened butter thoroughly.
Spread garlic butter on bread cut sides.
Heat olive oil in large skillet.
Cook sliced onions until golden brown.
Add bell peppers to onions.
Cook vegetables until tender and soft.
Season beef with salt and pepper.
Add seasoned beef to vegetable mixture.
Cook beef until browned and cooked.
Layer cheese on buttered bread halves.
Top cheese with beef-vegetable mixture evenly.
Wrap bread in aluminum foil completely.
Bake for 15 minutes until heated.
Remove foil for last 5 minutes.
Slice and serve immediately while hot.