1.Begin by mixing your sliced rhubarb and strawberries with sugar in a big bowl. Mix everything well, cover it tightly, and pop it into the fridge for at least 10 hours, or up to a full day. This rest lets the fruit soften and release its natural juices, making your jam more flavorful.

2.When you’re ready to cook, take the fruit mixture out and stir in the vanilla bean seeds for that special warm touch. Meanwhile, wash your jars thoroughly with hot, soapy water. Place them into your boiling water bath canner to keep them warm while you prepare the jam. Don’t forget to freeze a small plate, you’ll use it later to test the jam’s thickness.

3.Pour the macerated fruit and all its syrup into your favorite heavy pot, my go-to is a large Dutch oven. Add in the lemon juice and a pinch of salt, then bring the mixture up to a gentle boil over medium-high heat, stirring now and then.

4.As the jam starts boiling, you’ll notice some foam forming on top. Keep stirring every few minutes, adjusting the heat as needed. The liquid will slowly evaporate, and the fruit will break down, turning the mixture thicker and more jam-like over the next 10 to 15 minutes.

5.Around the 20 to 25-minute mark, your jam should be thickening nicely. If your fruit was especially juicy, it might take a bit longer, be patient! Keep stirring often, scraping the pot’s edges to prevent burning. If you have a candy thermometer, aim for about 210°F (99°C). If not, test by dropping a spoonful onto your frozen plate, tilt it and see how slowly it runs. If it holds its shape and wrinkles when nudged after half a minute, it’s ready.

6.Once your jam is ready, grab a warm jar from the pot and set it on a towel. Spoon in the hot jam, leaving a little space at the top. Clean the rim, then twist the lid on gently, just until it feels secure.

Carefully return the filled jars to the hot water. Once they’re all in, cover the pot and let them gently boil for 10 minutes. When that’s done, turn off the heat and let the jars sit in the water for another 5 minutes, this helps prevent spills when you take them out.

8.Lift the jars out and set them on a towel to cool completely at room temperature. Listen for the satisfying “pop” of the lids sealing, that’s your signal everything went perfectly.

9.After cooling, give the jars a quick check to ensure all lids have sealed tightly. If any jars haven’t sealed, keep them refrigerated and enjoy those first.

10.Finally, label your jars with the date, then store them in a cool, dark spot. Your homemade strawberry rhubarb jam will stay delicious for up to a year, if you don’t eat it all sooner.