1. In a blender, layer 1 cp strawberries, 1/2 cp blueberries, 1 cp yogurt, approx 1/2 cup milk, or more for thinner smoothie, and vanilla extract. Start out by mixing it til blended, then set on puree for one minute, longer for more processed smoothies.
2. This also freezes VERY well. I'll make a double batch and put 1 gallon away in the freezer, so I don't have to make it so often.