Description

A smooth, seedless blackberry cake filling made with fresh berries, sugar, and cornstarch. Perfect for layer cakes, jelly rolls, tarts, and more.

Ingredients

Scale

3 cups fresh blackberries (about 12 oz), or frozen thawed
3/4 cup granulated sugar, adjust to sweetness of berries
1 tablespoon lemon juice, freshly squeezed
2 tablespoons cornstarch
2 tablespoons water

Instructions

1. Mash the berries: Place the blackberries in a medium saucepan over medium heat. Use a potato masher to crush them thoroughly, releasing their juices.
2. Simmer the fruit: Add the sugar and lemon juice. Stir continuously until the sugar dissolves completely and the mixture comes to a rolling boil.
3. Cook down: Reduce the heat to a simmer and cook for 10 minutes, stirring occasionally. This softens the fruit, preparing it for straining.
4. Strain the seeds: Carefully pour the hot mixture through a fine-mesh sieve, pressing with a spatula to extract as much liquid as possible. Don’t rush this seedless process.
5. Thicken the puree: Return the smooth puree to the saucepan. In a small bowl, whisk the cornstarch and water to make a slurry.
6. Cook to thicken: Add the slurry to the puree, whisking constantly. Bring it back to a boil for 1-2 minutes until it thickens to a jam-like consistency.
7. Cool completely: Remove from the heat. Pour the seedless blackberry cake filling into a clean bowl to cool. This smooth blackberry cake filling will continue to thicken as it sets.

Notes

Swap lemon juice for lime juice, use arrowroot or potato starch instead of cornstarch, or try frozen blackberries. Add vanilla extract, cinnamon, or blackberry liqueur (like Chambord) for extra flavor.

For low-sugar, use a 1:1 baking sugar substitute. Store in an airtight container in the fridge for up to 2 weeks or freeze for up to 3 months. Stir before using; if too thick, warm gently.

Prep Time: 10 minutes
Cook Time: 20 minutes
Category: Dessert Filling
Method: Stovetop
Cuisine: American

Nutrition

Serving Size: 2 tablespoons
Calories: 62 kcal
Sugar: 14g
Sodium: 1mg
Fat: 0g
Saturated Fat: 0g
Unsaturated Fat: 0g
Trans Fat: 0g
Carbohydrates: 16g
Fiber: 1g
Protein: 0g
Cholesterol: 0mg

Keywords: seedless blackberry filling, blackberry cake filling, homemade fruit filling, berry filling, no seeds