Blueberry Coffee Cake

Streusel

• 2 tbsp unsalted butter, plus extra to grease
• 2 ½ oz sugar
• 2 oz brown sugar
• 1 oz all-purpose flour
• 1 tsp ground cinnamon
• ¼ tsp salt
• 1 pinch ground ginger
• 1 pinch ground nutmeg
• 1 oz chopped pecans

Cake

• 6 oz plain yogurt, unsweetened
• 2 oz vegetable oil
• 6 oz sugar
• 1 tsp vanilla extract
• 2 large eggs
• 8 oz all-purpose flour, divided
• 1 tsp baking powder
• ½ tsp baking soda
• ½ tsp salt
• 1 pinch ground nutmeg
• 10 oz fresh blueberries, plus extra to garnish
  of 10 oz frozen blueberries