Preheat oven to 220ºC (428ºF) fan-forced. Line a regular size 12-hole muffin pan with muffin liners. Set aside.
Melt butter and set aside to cool slightly.
In a large mixing bowl, add flour, baking powder, baking soda, and salt. Whisk until well combined. Set aside.
In a separate small mixing bowl, add instant coffee powder and pour in the boiling water. Whisk until the coffee dissolves.
Add both sugars and using a hand whisk, whisk the sugars into the coffee until well combined.
Pour in melted butter, milk, eggs, yogurt, and vanilla. Whisk until well combined and the eggs are beaten through.
Pour liquid mixture into the dry flour mixture and gently fold and mix until incorporated. Ensuring not to over-mix and no pockets or streaks of flour remain.
Spoon the batter into the muffin liners, filling them up to the top. Makes 12 regular-sized muffins.
Optional: Sprinkle flaked almonds on top of the muffin batter.
Bake for the first 5 minutes at 220ºC (428ºF).
After the first 5 minutes, reduce oven temperature to 180ºC (356ºF) and bake for a further 12-15 minutes until a toothpick inserted into the middle comes out clean.
Remove from oven and allow muffins to cool in pan for 10 minutes.
Transfer to a wire rack to cool completely.
Served warm or cool down and enjoy!
Store in an airtight container, in a dry dark pantry at room temperature, for 3-4 days.