01 - Preheat oven to 350°F. Line a 12-cup muffin tin with paper liners or lightly grease with cooking spray.
02 - In a large bowl, whisk together mochiko, almond flour, baking powder, baking soda, and salt until well blended.
03 - Dissolve instant coffee granules in the cooled French roast coffee, stirring until fully integrated.
04 - Whisk together sugar, eggs, milk, oil, melted butter, vanilla extract, and prepared coffee mixture until smooth and emulsified.
05 - Pour wet ingredients into dry ingredients. Gently fold until just combined; avoid overmixing to preserve tender texture. Fold in chocolate chips or nuts if using.
06 - Divide batter evenly among muffin cups, filling each approximately three-quarters full.
07 - Bake for 20 to 22 minutes until tops are set and a toothpick inserted into the center comes out clean.
08 - Let muffins cool in the pan for 5 minutes, then transfer to a wire rack to cool completely before serving.