113g1 stick unsalted margarine or butter, soft, cut in small pieces
3tablespoonsmild olive oil
1/2cuppacked dark brown sugarabout 2.4 ounces
1-1/2cuppacked haroset with Mr. BT's World Famous Thermonuclear Haroset (see below) or Faye's haroset
2large eggs
1/2cupsemi-sweet chocolate chips
1/3cupchopped walnuts
Instructions
Preheat the oven to 180C (350F). Lightly butter an 8-inch square baking pan. Line the pan with foil and butter the foil.
In a medium bowl, mix the ground walnuts, potato starch and salt.
In a large mixing bowl using a hand-held mixer, or in a stand mixer, beat the butter until it is smooth. Add the oil and the brown sugar; beat until the mixture is smooth and fluffy. Add the eggs, one by one, beating thoroughly on high speed after each one. Add 4 tablespoons of the ground walnut mixture and beat over low speed. Using a wooden spoon, stir in the remaining ground walnut mixture. Stir in the haroset and chocolate pieces.
Transfer the batter to the pan and spread it in an even layer. Sprinkle the chopped walnuts and pat them lightly so they adhere to the batter. Bake until the top browns lightly and a wooden pick inserted into the center comes out nearly clean, 18 to 22 minutes; if the wooden pick comes out chocolaty, test again. Cool the brownies in the pan on a rack.
Turn the brownies out gently onto a plate, then onto another plate or a cutting board so that the walnuts are on top. Using a sharp knife, cut it carefully into 16 bars. Serve at room temperature.