Hazelnut Streusel Bread

INGREDIENTS

for the streusel

3 tbsp

all-purpose flour

1/4 cup

(2oz/60g) packed light brown sugar

1 tsp

cinnamon

3 tbsp

unsalted butter

1/2 cup

(2&1/2 oz/75 g) dry roasted hazelnuts, roughly chopped

for the batter

1/3 cup

(2 oz/60 g) dry roasted hazelnuts

2/3 cup

(5 oz/155 g) granulated sugar

&1/4 cups (6&1/2 oz/ 200 g) all-purpose flour

2 tsp

baking powder

1/2 tsp

baking soda

1/2 tsp

sea salt

6 tbsp

(3 oz/90 g) unsalted butter, softened

large eggs

1 tsp

pure vanilla extract

3/4 cup

(6 oz/185 g) sour cream

1/2 cup

(3 oz/90 g) bittersweet chocolate chips

Zest of orange