Couldn't find a muffin recipe using self rising flour, perhaps you could use this recipe for muffins also.

BANANA NUT BREAD

3 c. flour (self rising)
1 c. oil
2 c. sugar
3 eggs
2 tsp. vanilla
2 c. mashed banana
1/2 c. chopped nuts

Preheat oven to 350 degrees. Grease 2 loaf pans. Cream oil,
sugar, eggs and vanilla. Add banana then gradually add flour
then mix in nuts. Pour into pans. Bake for one hour.