In a small sauce pan over low heat, add in the strawberries, water and sugar. Stir to combine. Leave simmering uncovered for 15 minutes. After approx. 15 minutes, smash the strawberries with an immersion blender or the back of a wooden spoon to break them up. Continue simmering over low heat for another 15-30 minutes, until desired thickness is achieved. After it is done cooking, stir in the lemon juice. You can serve warm or cold. Will keep in an airtight container in the fridge for 2 weeks, and can be frozen for 1 year.