Introduction

This homemade blueberry jam with vanilla is a delightful blend of sweet and tangy flavors, enriched with a subtle hint of vanilla. Perfect for spreading on toast, pairing with cheese, or adding to your favorite desserts, this jam brings a fresh burst of summer berries to your table.

Two slices of toasted bread are placed slightly overlapping on a white plate. Each slice is thickly spread with dark purple berry jam, which looks shiny and textured with whole berries, giving a rough surface. The toast has a golden brown color with a crispy edge, and some crumbs are visible on the plate. The plate sits on a yellow cloth with white polka dots, and the background is a white marbled surface. Photo taken with an iphone --ar 4:5 --v 7

Ingredients

2 dry pints blueberries (20 oz / 567 grams / roughly 4 cups)
16 oz sugar (454 grams / 2 slightly generous cups)
1.5 oz lemon juice (freshly squeezed, 43 grams / 3 tablespoons)
0.5 oz balsamic vinegar (14 ml / 1 tablespoon)
1/2 vanilla bean (split and scraped, or substitute 1 teaspoon vanilla extract at the end of cooking)

Instructions

Step 1: In a medium-sized, heavy-bottomed saucepan, combine the blueberries, sugar, lemon juice, balsamic vinegar, and the scraped 1/2 vanilla bean (if using).
Step 2: Use a potato masher or similar tool to partially crush the berries to help release their juices.
Step 3: Cover the pan and place it in the refrigerator overnight to allow the flavors to meld.
Step 4: The next day, remove the cover and set the pan over low heat for about an hour, gradually warming the mixture until it is hot.
Step 5: As the berries soften, mash them more thoroughly using your masher or another tool.
Step 6: Bring the mixture to a high simmer, then remove from heat and let it cool to a warm temperature.
Step 7: Cover again and refrigerate overnight.
Step 8: On the third day, uncover and heat the jam over medium to medium-high heat, stirring frequently, until it reaches a boil.
Step 9: Continue boiling and stirring almost constantly until the mixture reaches 223°F (106°C).
Step 10: Remove from heat, remove the vanilla bean, or stir in 1 teaspoon of good-quality vanilla extract if you prefer.
Step 11: Ladle the hot jam into clean jars, seal them with lids, and invert the jars until the jam cools to room temperature.
Step 12: Turn the jars right-side-up again. If you choose not to quick-can, simply let the jam cool, cover, and store in the fridge for up to 3 months.

Tips & Variations

For a quicker version, puree the berries to your desired consistency before cooking to save mashing time.
Substitute the balsamic vinegar with a mild apple cider vinegar if you prefer a less intense tang.
Use vanilla extract instead of a vanilla bean for convenience, adding it at the end of cooking to preserve flavor.
Add a pinch of cinnamon or nutmeg for a warm spice twist.

Storage

Store the jam in sterilized jars in the refrigerator for up to 3 months. If properly sealed and inverted while warm, it can be shelf-stable, but refrigeration is safest for homemade jam without commercial canning. Reheat gently on the stove or enjoy it cold straight from the jar.

How to Serve

A clear glass jar filled with thick, chunky dark purple blackberry jam, showing texture with whole and crushed berries; a spoon coated heavily with the jam is held above the jar, dripping slightly. In the blurred background, two slices of toasted bread topped with generous layers of the jam sit on a white plate. Everything is set on a surface with a white marbled texture. The light is bright and natural, highlighting the glossy, wet look of the jam. photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I use frozen blueberries for this jam?

Yes, frozen blueberries work well. Thaw them and drain off extra liquid before starting the recipe to avoid excess moisture.

How do I know when the jam is set?

The jam reaches the correct set point at 223°F (106°C). Alternatively, a chilled spoon test can help: a spoonful of cooled jam should wrinkle when pushed with your finger.