Preparation

• Mix the raspberries with the sugar in a large bowl and let it macerate at room temperature for 3 hours so the raspberries release their natural juices.
• Pour the contents of the bowl into a saucepan and add the lemon juice. Stir well to ensure the lemon juice is evenly distributed.
• Bring to a boil over medium heat for 5 minutes, occasionally stirring to prevent sticking.
• Strain the contents using a fine sieve, reserving the berries in a clean bowl.
• Return the strained liquid to the saucepan and bring to a boil again over medium heat for 5 minutes, stirring frequently.
• Add the reserved blackberries and bring everything to a boil over medium heat for another 5 minutes, stirring to prevent burning.
• Strain the contents again, separating the blackberries and resting them in a clean container.
• Return the strained liquid to the pot and repeat the process, boiling over medium heat for another 5 minutes, constantly monitoring.
• Add the blackberries for the last time and let the mixture boil for 5 minutes, ensuring the flavors blend completely.
• Remove any foam that may form on the surface with a skimmer to achieve a clean texture.
• Fill the jars with the hot mixture, leaving a small margin at the top.
• Have some sterilized jars and lids ready, and once the jars are full, place them upside down to create a vacuum, as we are making a few and this technique is appropriate.