Combine flour, sugar, baking powder, soda, salt and buttermilk powder.
Mix.
Cut in margarine.
Add water, raisins and orange peel.
Mix only until dry ingredients are moistened.
Gather dough into a ball and turn out onto floured board.
Knead lightly 12 times and divide into two equal parts.
Pat into circles approximately 1/2 inch thick.
Brush with glaze and cut each circle into 8 wedges.
Place wedges 1" apart on ungreased cookie sheet and bake at 425 about 13 minutes or until tops are brown.
The Over-Mixing Trap
Overworking the dough destroys the crumb structure of any pastry. When adding liquid to the dry ingredients, stop mixing the moment hydration occurs. Leaving small pockets of solid margarine intact creates steam pockets during baking, yielding flaky layers instead of dense biscuits. Handle the mass gently during the twelve designated kneads.
Thermal Dynamics at 425 Degrees
High initial oven heat is mandatory for reactive leaveners. Set the baking temperature precisely to 425 degrees Fahrenheit. This intense heat causes the baking powder and baking soda to react rapidly before the fats melt away completely. Watch for a golden brown top crust, which typically signals doneness around the thirteen-minute mark. Separate the wedges by at least one inch to ensure proper heat circulation and even browning.
Freezer Storage Dynamics
Unbaked cut wedges freeze exceptionally well on a lined sheet pan before transfer to an airtight bag. Bake frozen portions directly from the freezer by adding two to three minutes to the total thermal time. Glaze them immediately after pulling them from the heat source to lock in surface moisture.