Lightly grease a 2-cup (or similar size) microwave-safe baking dish or ramekin.
In a small bowl, gently toss the fresh blackberries with the liquid stevia and vanilla extract until coated.
Pour this berry mixture into your prepared dish.
In a separate small bowl, whisk together the almond flour and baking powder.
Add the cold, cubed butter and use a fork or your fingertips to cut it into the flour mixture until it resembles coarse, crumbly sand.
Sprinkle this topping evenly over the blackberries.
Microwave on high for 1½ to 2 minutes.
Check every 30 seconds, as microwave wattages vary. The cobbler is done when the berry filling is hot and bubbly and the topping is set.
Carefully remove the dish from the microwave and let it cool for at least 10 minutes. This allows the filling to thicken.
Serve warm, topped with a dollop of whipped cream, if desired.
Don't skip the 10-minute cool-down period. This step is crucial as it allows the hot berry juices to thicken into a delicious, syrupy sauce.
Taste your blackberries first. If they are particularly tart, you may want to add an extra drop or two of liquid stevia to balance the flavors perfectly.
