In a saucepan, place blackberries, ½ cup sugar, 1 tbsp cornstarch, pinch salt, 1 tsp lemon juice, and 1.5 tsp water.

Cook over medium heat, stirring, until the berries break down and the mixture thickens, about 8–10 minutes.

Puree with an immersion blender or in a blender until smooth. Strain if you want a silky gel (optional).

Bloom ¾ tsp gelatin in 1 tsp cold water (or follow package directions). Heat a small splash of the puree and whisk in the bloomed gelatin until dissolved. Stir that back into the puree. Chill until slightly thickened but still pourable.

Heat 2 cups milk, the split vanilla bean (scrape seeds into the milk), and 2 Earl Grey tea bags in a saucepan until just simmering. Remove from heat and steep for 10 minutes.

Remove tea bags (squeeze gently) and vanilla pod.

Whisk 4 egg yolks, ½ cup sugar, 4 tbsp cornstarch, and a pinch of salt until smooth and pale.

Slowly temper the egg mixture by whisking in about ½ cup hot milk in a steady stream. Return the tempered egg mix to the saucepan.

Cook over medium heat, whisking constantly, until it thickens and comes to a gentle boil, 1–2 minutes.

Remove from heat, whisk in 2 tbsp butter until melted and incorporated. Pass through a sieve for the smoothest cream. Cover surface with plastic wrap to prevent a skin and chill until cool.

Combine 1.5 cups flour, 0.5 cup sugar, and 1 tsp salt. Cut in 1 stick cold diced butter with a pastry cutter or in a food processor until mixture resembles coarse crumbs.

Mix egg yolk and 3 tbsp cold water, add to flour mixture and pulse until dough just comes together. Do not overwork.

Flatten into a disk, wrap, and chill for at least 30 minutes.

Roll dough to 1/8-inch thickness and line tart pans (makes about six 4-inch tarts or one 9-inch tart). Trim edges, dock bottoms with a fork. Chill shells 15 minutes in pan.

Preheat oven to 375°F (190°C). Line shells with parchment and fill with pie weights or dried beans. Blind bake for 12–15 minutes, remove weights and parchment, and bake 5–8 more minutes until edges are golden and centers are set. Let cool completely.

Fill cooled tart shells with chilled Earl Grey pastry cream, smoothing the tops.

Spoon or pipe the blackberry gelée over the cream in an even layer. Chill the assembled tarts for at least 2 hours to set.

Whip ¾ cup heavy cream to soft peaks and dollop or pipe on each tart just before serving. Garnish with fresh blackberries.