Melt the butter in a microwave-safe mug, then mix in the egg, Keto Chow, allulose, almond flour, and baking powder. Make sure the egg is completely blended.
Microwave on full power for one minute until cooked through. Careful: the mug may be very hot.
Allow the cake to cool, then top with the sliced strawberry and whipped cream or remove from the mug, cut the cake in half and layer with the strawberries and whipped cream.
Notes
Use a large mug so the cake has room to rise. No need to oil the mug; the cake should pull away from the sides as it bakes.