Veggie Subs | Savory

Ingredients

• 1 medium red onion, thinly sliced
• 3 medium bell peppers, seeded and thinly sliced
• 1 tsp dried oregano
• 4 tbsp olive oil, divided
• 4 (8-inch) sub rolls
• 1 (14 oz) jar quartered artichoke hearts, drained
• 8 pepperoncini, drained, stems removed and halved lengthwise
• 8 slices provolone cheese
• 2 plum tomatoes, very thinly sliced
• 1/4 cup balsamic vinegar