There is no plain flour available due to the current lockdown. I want to make the Banana Bread for my daughter’s birthday. Can I use self-raising instead? If so, what raising agents, if any, should I use?
Nigella's Banana Bread (from HOW TO BE A DOMESTIC GODDESS uses a combination of plain (all-purpose) flour, baking powder and bicarbonate of soda. As bananas tend to have a slightly leavening effect in baking we would usually recommend sticking with the ingredients listed in the recipe.
However there are current supply problems with flour in UK stores, due to the Covid-19 lockdown. So for this particular case we would suggest using the self-raising flour that you have, omitting the baking powder and adding just a pinch of bicarbonate of soda (baking soda). Please make sure that the self-raising flour hasn't passed its best before date. Unfortunately as we have not tried the Banana Bread in this form, we are unable to guarantee the results but the cake should rise enough with this combination. We would avoid adding too much bicarbonate of soda, as this can just cause the cake to rise up and then sink back again. Alternatively, if you can buy rice flour in a health food store, we would suggest trying Nigella's Gluten-Free Banana Bread as this is a wonderful version of banana bread that has been enjoyed by those who can eat gluten as well as those who need to avoid it.