Preheat the oven to 220°C fan/240°C conventional. Line every other hole of a muffin tin with liners. This recipe makes 9 regular-sized muffins, or 6 jumbo-sized muffins.
In a large bowl, stir the flour, sugar and baking powder together to combine. Make a well in the middle and set aside.
300 grams Self-raising flour, 180 grams Golden caster sugar, 1 teaspoon Baking powder
In a separate bowl, whisk the oil, eggs, buttermilk and vanilla extract together.
80 grams Vegetable oil, 2 medium Eggs, 250 millilitres Buttermilk, 2 teaspoons Vanilla extract
Pour the wet ingredients into the dry. Fold until the mixture is just combined. Take care not to overmix, a lumpy mixture with lots of air bubbles is what you're looking for.
Add a heaped tablespoon of plain mixture into each muffin liner to create a sturdy base (this will stop the blueberries from sinking).
Wash the blueberries (reserve a handful for later) and toss in a tablespoon of flour until well coated. Gently fold them into the mixture.
150 grams Blueberries
Divide the mixture evenly between the liners, filling each one to the top. Leave the unbaked muffins to rest on the countertop for 20 minutes* whilst the oven finishes pre-heating or you tidy up. This gives the raising agent in the mixture time to react, meaning fluffier muffins with bakery-style domed tops. It also gives the flour time to fully hydrate, making a thicker mixture that will keep those blueberries in place! *You can also cover the bowl with clingfilm and chill in the fridge for a few hours or overnight. Optional: Dot each muffin with a few extra blueberries and sprinkle over a little demerara or granulated sugar (the kind you'd put in your tea!). This way you're guaranteed to see juicy berries peeking out of the tops and the sugar will add a little sweet crunch.
Pop the muffins in the oven on the middle shelf. Bake for 6 minutes at 220°C fan, then with the oven door closed, reduce the temperature to 180°C fan and bake for a further 18-20 minutes. Your blueberry muffins should look golden brown, have risen tall and domed on top.
Let the baked muffins sit in the tin for 5 minutes, then lift them out onto a wire rack and leave to cool for another 30 minutes. Muffins are best enjoyed warm and freshly baked, but they will keep for 1-2 days at room temperature in a baking tin. Or, 4-5 if stored in the fridge.