Line a 15x10x1-inch baking pan with foil. Arrange crackers, side by side, in a single layer in prepared pan.
In a small saucepan, melt butter over medium heat. Add sugar; cook and stir until sugar dissolves. Bring to boiling, stirring constantly; boil gently, uncovered, for 2 minutes. Remove from heat. Stir in vanilla. Immediately drizzle mixture evenly over crackers. Evenly sprinkle with almonds and pistachio nuts.
Bake in 350 degree F oven for 10 to 15 minutes or until very lightly browned. Remove from oven. Immediately cut between crackers with a sharp narrow knife. Remove crackers from pan and cool on wire racks. Store, covered, in an airtight container for 3 days or freeze for up to 1 month. Makes 44 crackers.