- 2 tablespoons extra virgin olive oil (EVOO), divided
- 1 tablespoon butter
- 2 large onions, very thinly sliced
- Salt and freshly ground black pepper
- 1/3 cup pitted chopped black olives, niçoise or kalamata
- 1 tablespoon anchovy paste
- 2 pounds ground chicken
- 1 tablespoon dried herbes de Provence
- 1 teaspoon fennel seed
- 2 teaspoons lemon zest
- 2 cloves garlic, minced or finely chopped
- 4 slices Swiss cheese
- 4 crusty rolls, split and lightly toasted
- 4 red or green lettuce leaves
- Potato chips, for serving
Combine 1 tablespoon of the EVOO and the butter in a skillet over medium heat. Add the onions to the pan, season with salt and pepper and cook for 20 minutes to caramelize the onions. Stir in the olives and anchovy paste and cook for 2 minutes more. Remove from stove.
While the onions cook, combine the chicken with the herbes de Provence, fennel seed, lemon zest, garlic, salt and pepper. Heat the remaining 1 tablespoon of EVOO in a large nonstick skillet over medium-high heat. Form four patties and cook for 6 minutes on each side. Melt the Swiss cheese on each burger during the last 2 minutes of cooking time (loosely tent the burgers under foil to melt the cheese).
Serve the burgers on buns topped with lettuce and caramelized onion topping. Serve with potato chips alongside.