Wash the blackberries (please only use them when ripe!), Place them on kitchen paper and let them drain. Pour into a snap-bow glass (capacity at least 1.5 L) and layer in layers with the sugar. Gently squeeze the berries with a spoon so that the juice comes out and mixes with the sugar. Cover and leave in the refrigerator overnight so that the sugar is dissolved.
The next day, pour the sherry into the blackberry-sugar mixture and stir. Let it soak in a dark, cool place (not the fridge!) For about a week. Please shake again and again. After a week pour in the brandy and let the liqueur stand in a dark and cool place for another month, shaking it again and again.
The liquor is filtered through a cheesecloth and then bottled. It lasts around three to five months (if not drunk beforehand). It tastes best pure, slightly chilled.