In a small skillet, heat the beans over medium-low heat; stir in a splash of water.
In a large bowl, combine the sirloin, beer, onion, two-thirds of the garlic, the grill seasoning, chili powder and paprika. Divide into 4 equal portions, then form each portion into three 3-inch patties. Drizzle with EVOO.
In a small bowl, mash the avocado with half each of the red onion, jalapenos and cilantro. Mash in the lime peel and juice and the remaining one-third of the garlic; season the guacamole with salt. In another small bowl, toss the tomatoes with the mustard and the remaining half of the red onion, jalapenos and cilantro; stir, then season with salt. In another bowl, stir together the sour cream, hot sauce and cumin.
Preheat a large grill pan to medium-high. Add the patties and cook, turning once, for 6 minutes for medium. During the last minute of cooking, top each patty with 2 cheese slices and tent with foil to melt.
Top each bun bottom with a small spoonful of refried beans, a beef patty, some lettuce, guacamole, salsa, spicy sour cream and a sprinkling of olives; cover with the bun tops. Serve the sliders with any remaining toppings.
