Banana-Chocolate-Streusel Muffins | Desserts & Baked Goods | Umami

Ingredients

• Streusel
• 140g or 1 cup plus 2 Tbsp all-purpose flour
• 2g or 3/4 tsp ground cinnamon
• 360g or 2 cups packed light brown guess
• 110g or 1/2 cup unsalted butter, cold
• Muffins
• 210g or 1 2/3 cup flour
• 6g or 1tsp baking soda
• 1/4 tsp ground cinnamon
• 2.5g or ½ tsp fine sea salt
• 230g or 1 cup plus 2½ tbsp granulated sugar
• 100ml or 6 Tbsp plus 1 tsp canola oil
• 30g or 2 Tbsp sour cream
• 10ml or 2 tsp vanilla extract
• 3 or 4 super-ripe bananas, mashed (340g / 12 oz)
• 80g / 2¾ oz dark chocolate (55% to 64% cacao), chopped
• 1 medium-ripe banana, sliced