Preheat the oven to 450°F (232°C).

Cut four rounds of parchment to fit the bottoms of four 4-ounce ramekins. Butter each ramekin (use the extra butter called for in the ingredients), press a parchment round into the bottom of each, and butter the top of the parchment. Sprinkle a little flour into each ramekin, tilt and rotate to coat the buttered sides, and tap out any excess flour. Set ramekins aside.

Place the stick of butter (1 stick) and the chopped white chocolate (4 ounces) in a microwave-safe bowl. Microwave on medium power in 20–30 second bursts, stirring thoroughly between bursts, until the mixture is smooth and fully melted. Set the melted chocolate mixture aside to cool slightly so it is warm but not hot.

In a mixing bowl, beat the whole eggs (2), egg yolks (2), and sugar (1/4 cup) together until the mixture is pale and thick. You can use a stand mixer with the paddle attachment, a hand mixer, or whisk by hand.

With the mixer running on low (or whisking), slowly add the warm melted chocolate and butter to the egg mixture and combine until smooth.

Sprinkle the flour (2 teaspoons) over the batter and fold or mix just until no streaks of flour remain. Do not overmix.

Divide the batter evenly among the prepared ramekins.

Place the filled ramekins on a baking sheet and bake in the preheated oven until the edges are set but the centers remain soft and slightly jiggly, about 6–10 minutes (oven times vary; this recipe took about 9 minutes in the original testing).

Remove the baking sheet from the oven and let the ramekins sit on the sheet for 1 minute. Run a thin knife or small metal spatula around the inside perimeter of each ramekin to loosen the cakes.

Invert each ramekin onto a serving plate, wait 1–2 seconds, then lift the ramekin off. If a cake does not release, gently tap or shake the ramekin and try again.

Garnish with fresh raspberries, fresh mint, whipped cream, or vanilla ice cream if desired, and serve immediately.