1. Cream butter and brown sugar together in a 2-quart mixing bowl until light and fluffy. Add all remaining ingredients, except jam, and blend thoroughly. Press 1/2 of mixture into a well-buttered 8-inch square glass baking dish. Microwave, uncovered at Cook Cycle 1 (power level 7) for 9 to 12 minutes, or until mixture looks set.
2. Spread jam evenly over baked layer. Crumble remaining unbaked dough over jam and press lightly with finger tips. Microwave, uncovered, at Cook Cycle 2 (power level 7) for 6 1/2 to 9 minutes, or until set. Let cool. Cut into squares.