Chocolate Coffee Toffee Crunch Muffins

INGREDIENTS

For the muffins

2 cups

all-purpose flour

2/3 cup

packed brown sugar

1/2 cup

unsweetened cocoa powder, sifted

1 tbsp

espresso powder

2 tsp

baking powder

1/2 tsp

baking soda

1/2 tsp

fine sea salt

6 tbsp

unsalted butter, melted

1 1/2 cups

buttermilk

large eggs

1 tsp

vanilla extract

1 cup

semisweet chocolate chips

For the toffee crunch topping

1/4 cup

all-purpose flour

2 tbsp

brown sugar

1/2 cup

toffee bits (such as Heath)

1 tbsp

butter, at room temperature