Preheat the oven to 350°F (175°C).
In a bowl, Whisk eggs and sugar for 2–3 minutes until pale and slightly thickened.
Add melted butter and vanilla extract, then mix well.
Fold in the all-purpose flour gently to form batter.
Pour batter into a greased baking pan.
Bake for 22–28 minutes or until a toothpick inserted in the center comes out clean.
Allow the cake to cool completely before handling.
Toss sliced strawberries with sugar and let them rest.
In another bowl, rub cold butter with flour and sugar for crumbs.
Spread crumbs on a small baking tray and bake at 350°F (175°C) for 8–10 minutes until lightly golden and crisp.
Cut sponge cake into small cubes or rounds.
Layer cake, strawberries, and crumbs neatly in serving jars.