Preheat oven to 350°F. Line an 8 inch square pan with non-stick foil.

With a hand-held mixer, beat the butter, salt (if using) and brown sugar in medium bowl until smooth and fluffy. Beat in extract. Mix together the flour and baking powder, then add to the batter. Stir until well mixed, then stir in the oats. Reserve a heaping ½-cup for topping. Pat remaining crumbs into bottom of prepared pan.

Spread strawberry preserves evenly over crumb crust in pan. Toss the chocolate chips with the reserved crumb topping and sprinkle over the top

Bake for 30-35 minutes or until lightly browned. Cool on wire rack, then lift from pan and cut into 9, 16 or 18 bars.