Maple Walnut Blondies with Cocoa Streusel

Steps

1. Preheat the oven to 350°F (175°C) and line an 8-inch square pan with parchment, leaving an overhang.
2. Toast the walnuts on a baking sheet for 7 to 8 minutes until fragrant, cool, and chop. Set aside one quarter of the walnuts for the streusel.
3. Make the cocoa streusel first: in a small bowl, stir together about one seventh of the flour, all of the unsweetened cocoa powder, all of the granulated sugar and one third of the salt.
4. Pour about one quarter of the melted butter into the cocoa mixture and rub with your fingers into moist clumps, then mix in the reserved quarter of the walnuts. Chill the streusel while you make the batter.
5. For the batter, whisk the remaining three quarters of the melted butter with the brown sugar and maple syrup until glossy, then whisk in the eggs and vanilla until smooth.
6. In another bowl, whisk the remaining six sevenths of the flour, the baking powder and the remaining two thirds of the salt. Fold into the wet mixture just until no dry streaks remain.
7. Fold in the remaining three quarters of the walnuts and the chocolate chips, then spread the batter evenly in the pan.
8. Scatter the chilled cocoa streusel over the top and press it in lightly.
9. Bake for 28 to 32 minutes, until the edges are golden and a toothpick in the center comes out clean or with a few moist crumbs.
10. Cool completely in the pan on a rack, about 1 hour, then lift out by the parchment and cut into 12 bars.