Meatball Sliders with Tomato Sauce

Ingredients

• 3 tablespoons olive oil
• 4 leeks, light green and white parts only, cleaned and finely chopped
• 2 carrots, peeled and shredded, or 1 cup preshredded carrots
• 4 garlic cloves, minced
• 3 large eggs
• 1/4 cup Dijon mustard
• 1 cup chili sauce
• 1/2 cup finely chopped fresh parsley
• 1 cup freshly grated Parmesan cheese
• 1 cup fine dried bread crumbs (panko works well)
• 1 tablespoon Seriously Simple Seasoning Salt (page 217) or store-bought seasoning salt
• 1/2 teaspoon freshly ground black pepper
• 1 pound lean ground veal
• 1 1/2 pounds lean ground beef (15% fat)
• 1 1/2 pounds ground pork
• Two 26-ounce jars good-quality marinara sauce
• 1/4 cup finely chopped fresh basil
• 1 teaspoon finely chopped fresh thyme
• 2 teaspoons balsamic vinegar
• 60 mini-buns or slider rolls