Hull and slice the strawberries into a large bowl. Add the sugar and lemon juice and stir until coated. Let them sit at room temperature for at least 30 minutes while you make the biscuits.

Preheat the oven to 375°F and line a baking sheet with parchment paper.

In a large bowl (or food processor), whisk together the flour, sugar, baking powder, and salt.

In a measuring cup, stir together the egg, heavy cream, and vanilla until smooth. Set aside.

Add the cubed butter to the flour mixture. By hand, work it in with your fingertips or a pastry cutter until it looks like coarse, sandy crumbs. In a food processor, pulse to the same texture.

Pour in the wet ingredients and fold with a silicone spatula (or clean hands) until a dough forms. In a food processor, pulse just until the dough gathers into a ball around the blade.

Place the mounds on the baking sheet and bake at 375°F for 10–15 minutes, until risen and lightly golden at the edges. Let cool until just warm, not hot.

Add the cream, powdered sugar, and vanilla to a cold bowl. Beat with a hand mixer on low to combine, then increase to medium-high and whip until stiff peaks form. The cream should be billowy and smooth but hold its shape on the beater.

Slice a biscuit in half horizontally. Pile a generous ½ cup of strawberries and juice onto the bottom half.

Top with a heaping ¼ cup of whipped cream. Add the top half, then finish with a little more strawberries and cream if you like. Serve immediately.