Preheat a grill to medium high. Pour out one-quarter of a can of beer. Trim the base of a head of cauliflower so it can rest on the beer can but the florets still stay together. Brush melted butter all over the cauliflower and season with salt. Lay a double sheet of foil on the grill. Put the beer can on the foil and rest the cauliflower on the top. Cover the grill and cook until the cauliflower is browned and tender, about 1 hour. Remove the cauliflower and brush with melted butter mixed with hot sauce and grated garlic. Return the cauliflower to the beer can and grill 10 to 15 more minutes. Brush with more spicy butter and sprinkle with salt. Serve with blue cheese dressing.