Put the flour, sugar, baking powder and salt in a 12-ounce microwave-safe mug. Combine well with a fork. Add the milk, vegetable oil, vanilla, blueberries and strawberry and mix well.
Wipe the inside rim of the mug clean, then microwave on high for 90 seconds. Let cool for 1 to 2 minutes in the microwave, then top with whipped cream and the sliced strawberry.