Preheat oven to 375 degrees. Grease a 9x13 inch baking dish.
Combine flour, brown sugar, salt and baking powder in a food processor, pulse to combine. Add butter and process for 20 seconds. Pour the flour mixture into a large mixing bowl. Add oats, coconut and nuts, stir to combine.
Firmly press about ¾ of the crumb mixture into the bottom of the baking dish. Spread raspberry jam evenly over the crust. Sprinkle the remaining crumb mixture over the top, and lightly press it into the jam.
Bake 35 to 40 minutes or until the top is lightly browned. Cool at room temperature before cutting into bars.