In a large bowl, combine the ground beef, beer, grated onion, garlic, grill seasoning, chili powder, smoked paprika, and a pinch of kosher salt. Mix gently but thoroughly.
Form the mixture into 12 small patties, about slider size.
Heat a drizzle of extra-virgin olive oil in a large skillet over medium-high heat. Cook the patties 4-5 minutes per side or until cooked through and nicely browned. Remove from heat and set aside.
In a medium bowl, mash the avocado gently. Stir in the finely chopped red onion, jalapeños, cilantro, lime zest, lime juice, minced garlic, and salt to taste to create a vibrant avocado-lime salsa.
In a separate small bowl, mix the sour cream, hot sauce, ground cumin, and a pinch of salt for a spicy crema sauce.
Warm the refried beans in a small pot or microwave until heated through.
Slice the slider rolls in half horizontally. Spread a thin layer of yellow mustard on the bottom halves.
Layer each slider starting with a spoonful of warm refried beans, then a cooked beef patty.
Top the patties with a slice of pepper jack cheese, a spoonful of avocado salsa, and a drizzle of the spicy crema sauce.
Add a slice of yellow tomato and a small handful of shredded romaine lettuce.
Close each slider with the top half of the roll. Serve immediately and enjoy your flavorful 7-layer sliders!