Raspberry-walnut shortbread bars

1 ¼ cups flour
½ cup sugar
1 stick butter
½ cup raspberry jam
Topping:
2 large eggs
1/3 cup packed brown sugar
1 tsp. Vanilla
3 Tbls. Flour
1/8 tsp. Salt
1 cup chopped walnuts

Heat oven to 350 degrees. Combine flour and sugar in medium bowl; cut in butter using pastry blender or two knives until crumbly. Press on bottom of greased 9-inch square baking pan. Bake until edges are light golden brown, 18 to 20 ;minutes.
Spread jam over crust. For topping, beat together eggs, brown sugar and vanilla in bowl of electric mexer until smooth. Stir in flour and salt; add walnuts and mix well. Spoon topping over jam; spread carefully to cover. Return to oven. Bake until golden brown and filling is set, 20 – 24 minutes. Cool completely. Cut into bars.