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 sea salt until well blended.
03 - Dissolve instant coffee granules in the cooled French roast coffee in a small bowl, stirring until fully incorporated.
04 - In a medium bowl, whisk sugar, eggs, milk, oil, melted butter, vanilla extract, and coffee mixture until smooth and creamy.
05 - Pour wet ingredients into dry ingredients. Gently fold together until just combined; some small lumps are acceptable. Avoid overmixing. Fold in chocolate chips or nuts if using.
06 - Divide batter evenly among prepared muffin cups, filling each approximately 3/4 full.
07 - Bake for 20-22 minutes until tops are set and a toothpick inserted in 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.