Start by melting the butter, so it can cool down while preparing the rest of the ingredients.
40 g butter
In a bowl, sift the all-purpose flour, granulated sugar, baking powder and salt. Add the mini chocolate chips and stir it all together.
160 g all-purpose flour, 100 g granulated sugar, 1 ½ teaspoon baking powder, ¼ teaspoon salt, 85 g mini chocolate chips
In another mixing bowl add the sour cream, milk, egg, vegetable oil, vanilla extract and melted butter. With a hand whisk, mix it together until combined.
50 g sour cream or full-fat greek yoghourt, 100 g whole milk, 1 large eggs, 2 tablespoon vegetable oil, 1 teaspoon vanilla extract
Pour the wet ingredients into the dry ingredients and gently stir it together with a hand whisk or rubber spatula.
Cover the bowl with some plastic wrap and let the batter rest for 1 hour.
While the batter rests, preheat the oven to 220ºC/425ºF conventional oven. Prepare a 12-cup cupcake pan with 6 cupcake liners, only lining every other cupcake hole, as it helps them to dome up. Grease around the edge of the cupcake holes, for the muffins to release easily.
Using a large ice cream scoop, divide the muffin batter into the 6 cupcake liners, so each cupcake holder is filled to the top. Be careful not to deflate the batter, so try not to mix it around it too much. Top the muffins with lots of mini chocolate chips and cane sugar and bake them for 7 minutes and then reduce the heat to 175ºC/350ºF and further bake for 10-12 minutes.
40 g mini chocolate chips, 1-2 teaspoon cane sugar
Let the muffins cool in the hot pan on a wire rack. After 5 minutes, gently remove the muffins from the pan. You might need to use a knife to help release the muffins from the pan. Let them cool down additionally for 10-15 minutes before eating! They are best enjoyed warm.