In large food processor bowl, thoroughly combine flours, salt, baking powder, cream of tartar, and sugar.
Add margarine in pieces and briefly pulse just until mixture is coarse and crumbly.
Add the fat free half-and-half and briefly pulse just until blended (do not overmix).
Turn onto a lightly floured surface and knead gently 4 or so times.
Pat dough until about 1/3- to 1/2-inch thick. Using a 2 1/2- to 3-inch round cutter, cut out biscuits and place them on a baking sheet coated with canola cooking spray.
Bake until nicely brown, about 12-14 minutes. Let cool.
Meanwhile, add 2 cups sliced strawberries, brown sugar, and vanilla to food processor and pulse until a strawberry puree is created (about 5 seconds).
Split a biscuit in half and place both halves, cut side up, on a dessert plate. Drizzle about 1 tablespoon of the strawberry puree mixture over the top of each half. Top both halves with a total of 1/2 cup of strawberry slices and a dollop of light whipped cream.