- Lay both slices of the bagel facedown. Brush with olive oil and sprinkle half of oregano and dash of sea salt on both pieces.
- Flip over and spread pesto sauce on the cut side of the bagel. Layer bottom half of bagel as follows: chicken, red onion, red pepper, mushrooms, cheese, oregano, tomato, salt, pepper and basil leaves. Place top half of bagel onto bottom half and press firmly.
- Place the sandwich in a heated Panini grill and cook until cheese melts and the bagel bread is toasty brown and has grill marks. Remove, cut and serve!