Combine strawberries, lemon zest and juice, as well as 1/4 cup of sugar in a blender. Blend until smooth. Pour into a separate container and set aside. Rinse out blender.
Combine pineapple, coconut milk, vanilla, remaining 1/4 cup of sugar and ice cubes in the blender. Blend until smooth.
Starting with the pineapple mixture, pour into glasses, stopping to add a couple spoonfuls of the strawberry mixture intermittently. Finish with a dollop of strawberry mixture on top. Garnish with strawberries, pineapple slices and lemon zest. Yields about 6 mocktails, depending on size of the glass.
Tip: If you want a thicker, more smoothie-like consistency, then cut the pineapple and freeze it for several hours prior to making pina coladas. Then omit the ice when blending.