Sweet and ever-so-slightly tart, strawberry jam ranks among the top spreadable fruit flavors. When the pick-your-own season begins and supermarket shelves are abundant with the juicy, scarlet berry, it signals the start of summer, and it’s an opportunity to get your jam on. Here, just three ingredients—strawberries, sugar and lemon juice—make a simple jam that’s not overly sweet. However, it is crucial to have an instant-read thermometer on hand and to keep a watchful eye on the simmering temperature so the fruit’s natural pectin can do its thickening magic. In the off-season, frozen berries are a perfectly suitable stand-in for fresh, since they’re often picked at peak ripeness. This simple jam will last in the fridge for up to two weeks (for larger batches and a longer shelf life, consider canning it). Spread strawberry jam on crumpets, make an extra-special dessert, or, if you can’t wait for it to cool, spoon it warm over some ice cream.