Add the strawberries, blueberries, blackberries and water to a saucepan over medium heat. Simmer for 15 minutes, until reduced by about half.
Strain out the berries. Measure the liquid and add an equal amount of sugar — about 1 cup. Stir until fully dissolved while the liquid is still hot.
Let cool completely before using or storing.
Notes
Berry options: You can swap in raspberries, cranberries or cherries for any of the berries listed — just keep the total amount to about 1 cup.Other mix-ins: Try adding a few sprigs of mint or basil, or swap the berries for peaches or other stone fruit for a different flavor entirely.For a thicker syrup: Add up to twice as much sugar if you want a thicker consistency for pancakes or other uses. Keep in mind that berries have natural pectin and sugar, so you may need a little less than you think — too much and it can get gelly.Precise method: For the most consistent results, simmer until reduced by half, measure the liquid, then add an equal amount of sugar rather than measuring a flat cup.Storage: Store in an airtight jar in the fridge for up to 2 weeks.