In a medium saucepan, combine sliced strawberries, 1/3 cup maple syrup and freshly squeezed juice from 1/2 lemon. On medium heat, bring the mixture to a boil, stirring occasionally. 

Reduce heat and simmer 15 minutes or until sauce is thickened. Remove from heat and cool to room temperature. 

The sauce will thicken up as it cools and if you are storing it in the refrigerator, it will thicken even more so be careful to get the consistency you want.