Preheat the oven to 350 degrees F.
Prepare your muffin pan by greasing it with Pam, butter, or vegetable oil.
Heat up the half and half in a small sauce pan for about a minute until it is warm. Remove from the heat and add in your coffee. Let the coffee steep for 10 minutes.
While the coffee is steeping, mix together the sweet rice flour and baking powder. Set aside.
In another bowl, mix together the butter, sugar, vanilla extract, and eggs. Set aside.
After the coffee steeps for 10 minutes, use a coffee filter or a paper towel to filter the liquid into a liquid measuring cup. Make sure you have 1 1/2 cup of coffee milk. Add the coffee milk to your wet ingredients from step 5. Whisk together.
Add your dry ingredients from step 4 into your wet ingredients. Make sure to sift the dry ingredients into your wet ingredients to avoid clumping. Mix with a spatula until well combined.
Use a large cookie scoop to divide the batter evenly between your muffin molds.
Sprinkle the top with black sesame seeds. (optional)
Bake for 20-25 minutes until a toothpick comes out clean.
Let muffins cool for 10 minutes before serving.