Picadillo Sliders with Garlic Mayo

Name: Picadillo Sliders with Garlic Mayo
Ingredients: 1/2 cup mayonnaise; 3 cloves garlic, 1 finely grated and 2 chopped; Kosher salt and freshly ground black pepper; 3 tablespoons olive oil; 1 small onion, chopped; 1 1/2 pounds ground beef; 1/2 cup slivered almonds, coarsely chopped; 1/2 cup pitted green Spanish olives, coarsely chopped; 1/2 cup raisins, coarsely chopped; 1/2 cup tomato sauce; 1/2 teaspoon ground allspice; 1/2 teaspoon ground cinnamon; 16 potato slider rolls, split; Lettuce leaves, for topping