Ingredients
¼ cup grain mustard
½ cup balsamic vinegar
2 cloves garlic, chopped
¼ cup extra-virgin olive oil
1 tsp salt
1 tsp black pepper
2 tbsp olive oil
2 lb flank steak
1 red bell pepper, halved and seeded
1 green bell pepper, halved and seeded
1 red onion, cut into ¼-inch slices
10 oz BBQ sauce
3 loaves French bread
1 lb fresh mozzarella cheese, sliced or grated
Preparation
Mix mustard and balsamic vinegar in a small bowl.
Add garlic, drizzle in olive oil while mixing.
Season mixture with salt and pepper to add taste.
Place steak inside a bowl.
Pour in ¾ of the marinade inside bowl and combine.
Marinate steak at room temperature for at least 30 minutes.
Coat onions with BBQ sauce.
Saute onions and pepper in oil until golden brown.
Once golden brown, remove from pan to keep warm.
Remove steak from the marinade and grill.
After 5 minutes, turn steak over to sear its other side. Transfer steak to a cutting board. Let it cool for 10 minutes before slicing.
Cut bread lengthwise and toast for a few minutes.
Brush the remaining marinade on both sides of the bread.
Arrange steak on one half of the bread, then season it with peppers and onions.
Top steak with cheese, then cover it with other half of the bread.
Cut the entire sandwich into 4 pieces and serve.
