Spinach Pesto Stuffed Burgers

Ingredients

Spinach Pesto:
1 large clove garlic
2 cups packed bagged ready-to-eat baby spinach (about 2 ounce
1/4 teaspoon Kosher salt
1/4 teaspoon freshly ground black pepper
3 tablespoons extra-virgin olive oil
1/4 cup freshly grated Parmesano-Reggiano cheese

Roasted Pepper Aioli:
1 large clove garlic
5 ounces roasted pepper from 7 oz. jar, drained
1 tablespoon mayonnaise (good quality reduced-fat may be used)
1/2 teaspoon Kosher salt
1/4 teaspoon freshly ground black pepper

Patties:
2 pounds ground sirloin
1/2 cup finely chopped onion
3 large cloves garlic, minced or pressed
1-1/2 tablespoons finely chopped fresh basil, or 1 teaspoon dried leaves
2-1/2 teaspoons finely chopped fresh oregano, or 3/4 teaspoon dried leaves
1/4 cup finely chopped fresh Italian flat-leaf parsley
3/4 teaspoon Kosher salt
1/2 teaspoon red pepper flakes
2 tablespoons tomato paste (I use double-concentrate from a tube)
1 tablespoon extra-virgin olive oil

olive oil for brushing grill, patties, tomatoes, radicchio and bread
6 (1/2" thick) large yellow tomato slices (may use red if yellow are not available)
6 slices Provolone cheese
12 radicchio leaves
6 (6" squares) foccacia bread or Ciabata bread, cut horizontally in half
or Ciabata bread

Instructions

Directions:

Preheat a gas grill to medium-high.

To make the Spinach Pesto: With food processor running, drop garlic through feed tube; process until minced. Add salt, pepper and olive oil; process until smooth. Add Parmesan cheese and pulse until mixed in. Remove from processor; set aside. Wash out processor.

To make the Roasted Pepper Aioli: With food processor running, drop garlic through feed tube; process until minced. Add peppers, mayonnaise, salt and pepper; process until smooth. Remove from processor; set aside.

To make the Patties: Combine all ingredients in a large bowl; mix gently to combine. Form mixture into 12 thin patties of equal size. Spoon one heaping tablespoon of Spinach Pesto onto 6 patties, leaving a 1/2" border.
Top with remaining 6 patties, pressing edges to seal. Oil grill rack. Brush both sides of burgers with olive oil. Place burgers on grill and cook 4 to 5 minutes on each side, turning once. Brush tomatoes with oil; sprinkle with salt and pepper; grill 3 to 4 minutes, turning once. Brush radicchio with olive; grill 2 to 3 minutes. Brush cut sides of bread with olive oil. Place cut side down, around edges of grill to toast. When burgers have a minute or so to go, place a slice of cheese on top and close grill lid.

Place a patties on bottom slice of bread; add tomato and radicchio. Spread a heaping tablespoon of aioli on top bread slice and place on burger. Makes 6 burgers.