Keto blueberry mug cake is full of fresh blueberries, lemon zest, and flavor! This is quick to make and satisfies your sweet cravings while sticking to your low carb or gluten-free diet plan!
Place dry ingredients in a large microwave-safe mug and stir together with a fork.
Add egg, butter, olive oil, and extract. Mix well.
Add fresh blueberries and lemon zest and fold gently into the batter.
Place mug in microwave and heat for 1 minute 15 seconds. If the top of mug does not look cooked, continue to cook in 15-second increments. The top should be soft to the touch.
Carefully remove mug from microwave and place upside-down on a plate. Let muffin fall to the plate.
Slice mug muffin in half and toast and spread with butter or cream cheese.