Pre-heat your oven to its highest setting (temperature will be reduced when muffins go in). Prepare your muffin tray by lining with cases and set aside.
Sift together into a bowl: flour, sugar, baking powder and bicarbonate of soda, and set aside.
In another bowl put all your wet ingredients: peanut butter, oil, egg, milk, vanilla extract and mix well.
Sift all your dry ingredients into the bowl with the wet ingredients, when sifted add peanut butter chips and fold mixture 15 times ONLY.
Spoon your mixture into your muffin cases so they are each a good 3/4 full and place in your oven on the middle shelf, reduce temperature to 170 C / Gas 3 and bake for 25 to 30 minutes until the tops are firm to touch.
Place a roasting tray or any oven proof container full of water on the bottom shelf of your oven when baking your muffins; it will help keep them really moist.
Hold your sieve high above bowls when sifting dry ingredients; this will make your muffins really light.
To help your peanut butter chips keep their shape in the muffins, freeze them before using.
MOST IMPORTANT! Remember to only stir your mixture 15 times; this is the key to great muffins. Don't be tempted to over-stir no matter what your mixture looks like.
Used different ingredients.
These are lovely. However i had sooo much batter left over, that i made a cake!! i used 7 teaspons of coco powder. (More for your own taste) 1 mashed banana. And chocolate chips. (Well chopped up chocolate bars) Just as much as i liked really. Use your judgement. I then added some water to make the mixture slightly runnier.
Poured the whole thing into a cake tin.
Boom!!! Gorgeous Moist, Peanut Butter, Chocolate and Banana cake!! (I use a very small cake tin, about 6" across. - 07 Jun 2010