Plum and vanilla jam

Ingredients:

• 0.7 kg firm ripe plums, cut into 2.5 cm pieces (with skin)
• 2 and 1/4 cups sugar
• 2 vanilla pods, split lengthwise, then crosswise
• 4 small cinnamon sticks
• 1 lemon
• 0.7 kg firm ripe plumcots or apricots, cut into 2.5 cm pieces (with skin)

Preparation:

1. Start with ours step-by-step guide to canning.
2. Place the plums, sugar, vanilla, and cinnamon sticks in a large, wide saucepan. Squeeze the lemon juice and strain it through a sieve into the saucepan. Heat over medium-high heat, stirring occasionally, until the sugar dissolves and the mixture comes to a boil, about 10 minutes.
3. Reduce heat to medium and continue cooking, stirring occasionally, until a candy or deep-fry thermometer registers 212°F (104°C), about 30 minutes. To ensure the mixture has reached gelatinization temperature, spoon a small amount onto a chilled plate and place it in the freezer. The liquid should set; if not, continue cooking and repeat this test in a few minutes. Remove the pan from the heat and let cool for 30 minutes.
4. Meanwhile, sterilize four 240 ml jars with lids.
5. Return the plum jam to medium heat. Stirring constantly, bring to a boil, then add the plumcots. Reduce the heat to medium and simmer until softened, about 5 minutes. Remove the cinnamon sticks.
6. Fill the jars with jam, leaving 1 cm from the brim, then close the lids and preserve.