Vegan Blueberry Muffin Mug Cake

"Why have a breakfast rut, when it's so easy to pull together a quick mug cake? I love the convenience of throwing a few ingredients together and coming out with something special that mug cakes provide. This Blueberry Muffin Mug Cake is vegan, gluten-free and food allergy-friendly, because it is free of the top-8 allergens. You can make as many or as few as you need, as each is a single serving -- no leftovers! While fresh blueberries are hit or miss at the grocery store where I live right now, when I don't have fresh, I can use frozen. I hope you enjoy this quick treat!"