Make the strawberry puree. For frozen strawberries, cook them with a splash of water in a small saucepan over low heat until soft and broken down, then blend smooth and pass through a fine mesh sieve. For fresh, just wash, hull, blend, and strain. You want about 1/2 cup of smooth puree — no seeds, no pulp.
1/2 cup strawberry puree
Reduce the puree. Add the puree to a small saucepan over medium-low heat. Simmer gently for about 10 minutes, stirring every now and then so the bottom doesn't burn. You're aiming for around 30% reduction — it should look glossy and noticeably thicker, ending up at roughly 1/3 cup.
Melt the chocolate in the puree. Take the pan off the heat. Add the chopped white chocolate to the hot puree and leave it for 1–2 minutes without stirring. Then stir gently until the chocolate melts in. If a few stubborn pieces remain, return the pan to low heat for a minute or so, stirring constantly, just until smooth. Spend as little time warming the chocolate as possible — the residual heat from the puree should do most of the work.
2/3 cup white chocolate, chopped
Cool the mixture. Cool to warm but not hot — check by tasting. If you didn't have to return the pan to the stove, it should be good to go right away.
Beat the cream cheese. Beat the cream cheese with the vanilla, lemon juice, and salt until completely smooth. Scrape down.
8 oz full-fat block cream cheese, room temperature, 1 tsp vanilla bean paste, 1 tsp lemon juice, 1 pinch salt
Combine. Add the cooled strawberry-white chocolate mixture to the cream cheese and beat on low until smooth and a uniform pink. Scrape down as needed.
Whip the cream. Whip the cold heavy cream to soft-medium peaks. Don't overwhip — you want it to fold in cleanly, not stiffen the filling.
1/3 cup cold heavy cream
Fold together. Stir about a third of the whipped cream into the strawberry mixture to lighten it. Then gently fold in the rest with a silicone spatula until no streaks remain.
Taste and adjust. Taste the finished mixture. If it needs more sweetness, sift powdered sugar over the top in small amounts and gently fold in with the spatula. If it needs more brightness, add a touch more lemon juice. Taste after each addition — most batches need little to none.
powdered sugar, sifted
Fill the cups. Spoon or pipe the filling over the chilled crusts, dividing evenly between the 5 cups. Smooth or swirl the tops.
Chill. Refrigerate for at least 4 hours so the white chocolate has time to fully set. Overnight is ideal.
Top and serve. Finish with fresh sliced strawberries, a spoonful of reduced puree, freeze-dried strawberry powder, white chocolate shavings, or a drizzle of strawberry coulis.