Polpetti Burgers

• Extra virgin olive oil
• 2 onions, cut into 1/4-inch dice
• Kosher salt
• 2 cloves garlic, smashed and finely chopped
• 1/2 pound ground beef
• 1/2 pound ground veal
• 1/2 pound ground pork
• 2 tablespoons fresh rosemary, finely chopped
• 1/2 cup freshly grated Parmigiano
• 1/4 cup bread crumbs
• 1 large egg
• 4 large hamburger buns
• 4 slices Fontina cheese
• Mayonnaise
• 2 cups baby arugula
• 1 large tomato, sliced
• Pickled Red Onions (page 161) or 1 red onion, thinly sliced

1. Coat a large saute pan with olive oil, add the onions, and bring to medium heat.
2. Season the onions with salt and cook until soft and aromatic, 8 to 10 minutes.
3. Add the garlic and cook for another 2 to 3 minutes, stirring frequently.
4. Remove from the heat and let the mixture cool.
5. In a large bowl, combine the cooled onion mixture with the beef, veal, pork, rosemary, Parmigiano, bread crumbs, egg, and 3 to 4 tablespoons of water.
6. Mix well and season generously with salt.
7. Make a 1- to 2-inch tester patty.
8. In a small saute pan, heat a bit of oil and cook the patty.
9. When its cool enough, taste it to make sure its deliciousif its not, reseason.
10. When the tester tastes fabulous, form the meat mixture into four equal patties.
11. Preheat a grill or coat a large saute pan with olive oil and bring it to medium-high heat.
12. Cook the burgers for 4 to 5 minutes per side.
13. Toast the buns on the grill or in the toaster.
14. While the second side of the burger cooks, place a slice of cheese on top and let it melt.
15. Schmear each side of the bun lightly with mayonnaise, place a burger on each bottom half, garnish with the arugula, tomato, and onions (pickled or otherwise), top with the other half of the bun, and serve.

extra virgin olive oil, onions, kosher salt, garlic, ground beef, ground veal, ground pork, fresh rosemary, bread crumbs, egg, buns, cheese, mayonnaise, baby arugula, tomato, red onions

Taken from www.epicurious.com/recipes/food/views/polpetti-burgers-378187 (may not work)