The etymology of "Welsh rarebit" is about as elusive as the animal in its alternative name: "Welsh rabbit." The dish, available at McGonigel's Mucky Duck [2425 Norfolk, (713)528-5999], is considered pub grub, but Duck owners Rusty and Theresa Andrews have elevated it to a higher plane. This tangy appetizer for two (or entrée for one) starts with day-old bread soaked in Guinness, then covered in sharp cheddar and baked until the top and edges are crusty and slightly brown. Served in a small casserole dish surrounded by toasted baguette slices, this concoction is garnished with thickly sliced hickory-smoked bacon and sautéed mushrooms on top. So why is it called Welsh rabbit? Some say it's because rabbit hunters ate it regularly. Others claim a Welsh chef once tried to pass it off as rabbit. Whatever the reason, the name should not scare away vegetarians who like good, gooey cheese.