2cupswhole wheat pastry flourOR 1 cup unbleached + 1 cup whole wheat OR all unbleached
3/4cupabout 1/4 pound bittersweet chocolate, chopped or chips (divided)
3/4cupabout 1/4 pound white chocolate, chopped or chips (divided)
3/4cupabout 1/4 pound milk chocolate, chopped or chips (divided)
Preheat the oven to 300°.
Line a 9-by-13-inch baking pan with parchment paper, leaving the long sides with longer pieces to be able to lift the brownies from the pan after cooking.
In a medium saucepan, melt the butter with the unsweetened chocolate (OR oil/cocoa powder mixture) over low heat, stirring until melted (or carefully microwave until melted). Set aside to cool some.
In a large bowl, mix the sugar with the eggs, vanilla and salt. Add the melted chocolate-butter mixture and whisk until smooth. Add the flour and stir well. Fold in 1/2 cup each of the three chocolates.
Spread the batter evenly in the prepared pan.
Place the remaining 1/4 cup of each chocolate separately in 3 small microwave-safe bowls and melt. Using a spoon, drizzle the melted chocolates over the batter. Using a table knife, make swirls in the batter for a marbled effect.
Bake 35 minutes, rotating the pan halfway through, until the tops are shiny and set. Do not over bake or the edges will be dry. These are a fudgy brownie.
Transfer the brownies to a wire rack to cool completely. Use parchment handles to lift from the pans and use a pizza cutter or large knife to cut into squares.
Make-Ahead: Cut into sizes for gifting, wrap in plastic wrap (or cut for serving and store in freezer-safe container) and freeze for 3-4 months.