In a mixing bowl, combine the ingredients (except for the blueberries). Whisk the ingredients together until well combined.
Add the blueberries to the bowl. Gently fold in them, distributing them evenly throughout the batter.
Once the batter is well-mixed and consistent, carefully pour it into a tall-sided microwave-safe mug. Fill the mug about halfway to two-thirds full to allow for expansion as the muffin cooks.
Place the mug in the microwave. Set the microwave timer for 90 seconds. The cooking time can vary based on the wattage of your microwave, some microwaves may require up to 2 minutes for the muffin to fully set.
Keep an eye on the muffin as it cooks. It should rise and become soft and bouncy in texture. If the muffin looks undercooked after the initial time, continue microwaving in short intervals (e.g., 15-30 seconds) until it’s fully cooked and no longer wet in the center.
Tips
Recipe Development + Food Photography by Jessica Reynolds-Corden from Jessica Eats.