Blackberry Rhubarb Bread

Preheat oven to 180ºC (350ºF). Grease two loaf pans, about 23×12 cm (9×5 inches).

Place brown sugar, oil and egg in a large bowl and beat until blended. Add buttermilk, yogurt and vanilla; blend again.

Mix together flour, baking soda and salt. Gradually add to the sugar mixture.

Halve the blackberries if they are large and fold in the mixture together with sliced rhubarb. Divide mixture between the two loaf pans.

Melt butter in a small pan. Remove from the heat and stir in cinnamon and sugar. Sprinkle the clumps over the batter in the pans and bake for 50 minutes. Use the toothpick test; it should come out with only a few crumbs on it.

Let cool in the pan for about 10 minutes, remove and let cool completely on a wire rack.