In a pot of boiling water cook soba for about 8 to 10 minutes or according to package directions. until done. While soba is cooking heat butter in a small skillet until it is golden brown; you want the flavor of the butter. Drain soba and return to saucepan and toss with golden butter and 4 tablespoons of sour cream, chives and half of caviar. Portion out and top with more sour cream and caviar if you wish.