It's not hard to come by a fabulous gourmet brunch in Berkeley, a town that helped define the genre. But when 900 Grayson opened its doors in west Berkeley last spring, owners really threw down the gauntlet. Their Idaho hash browns‹heavenly golden discs of crisp shredded potato‹remind you how few places still bother to make them right. Dishes with names such as Demon Lover (a tangy, whole wheatinflected waffle topped with juicy, spicy Fulton Valley fried chicken and cream gravy) live up to their dramatic titles. On the lunch side, it¹s hard to beat the shoestring onion and house-made barbecue saucetopped Grayson burger. The owners aim to open for dinner down the road. We hope they succeed. Breakfast and lunch Mon.Sat., brunch Sat.