Preheat oven to 360 degrees F (180 degrees C).
Place cupcake liners in muffin pan and set aside.
Sift Self-Rising Flour (240 gram) into a large bowl, add Butter (100 gram), Brown Sugar (140 gram), Lemon (1), Lemon Juice (1 tablespoon), Vanilla Extract (1 teaspoon) and Egg (2). Beat with electric mixer on low speed until ingredients are combined. Then increase speed to medium, beat mixture until smooth. Stir in Banana (350 gram) and mix well. Lastly add in in Dried Pitted Prunes (100 gram) and fold well with a rubber spatula.
Scoop banana mixture into muffin pan to 3/4 full and bake in preheated oven for about 25 minutes or test with a skewer till it comes out clean.