Preheat oven to 170 degrees. Keep a large loaf pan greased and floured.

Combine all the flours, soda and salt in a bowl. Mix well and set aside.

In a larger bowl, beat butter and sugar till fluffy. Add in the eggs one at a time and beat after each addition.

Add in the vanilla essence, yogurt and mashed bananas and beat for a minute.

Now add in the dry ingredients and fold till all moist.

Divide the batter into half.

Into one half, add the cocoa powder and fold in.

Layer into the prepared loaf pan. I put the plain batter in first and then put the chocolate batter and gave a swirl with a fork.

Bake for an hour till the skewer comes out clean. Ensure to cover the top of the tin with an aluminium foil at 40 minutes, if you find the top is getting dark.

Cool in the tin for 10 minutes, before flipping onto a cooling rack, to cool completely.

Slice and enjoy with a cup of coffee!