Directions

1. 1

   Preheat your oven to 400°F. Generously brush the interior of four soufflé ramekins with softened butter. Coat each ramekin with a thin, even layer of granulated sugar, tilting and rotating to coat all sides. Tap out any excess sugar. This sugar coating helps the soufflés rise evenly and develop a golden top.

2. 2

   Place the prepared ramekins on a baking sheet and set aside. Blend the thawed frozen raspberries in a blender until completely smooth, then strain the puree through a fine-mesh sieve to remove all seeds. Reserve 4 ounces of the strained raspberry puree for the soufflé base.

3. 3

   In a large mixing bowl, whisk together the 4 egg yolks and 2 1/2 ounces of granulated sugar until the mixture becomes thick, creamy, and pale yellow in color, approximately 2–3 minutes of continuous whisking.

4. 4

   Gently fold the reserved 4 ounces of raspberry puree and the lemon juice into the yolk mixture until well combined. Set this raspberry base aside.

5. 5

   In a clean, dry bowl of a stand mixer fitted with a whisk attachment, combine the 4 egg whites, cream of tartar, and salt. Begin whisking on low speed until the mixture becomes foamy, about 30 seconds. Increase the speed to medium-high and gradually add any remaining granulated sugar while whisking continuously. Beat until the egg whites form soft peaks that curl slightly when the whisk is lifted—do not overbeat or they will become dry and grainy.

6. 6

   Using a rubber spatula, gently fold about one-quarter of the beaten egg whites into the raspberry yolk mixture to lighten it. Then fold in the remaining egg whites in two additions, folding gently but thoroughly until mostly combined. A few white streaks may remain, but do not overfold or you will deflate the mixture.

7. 7

   Carefully pour the soufflé mixture into the center of each prepared ramekin, dividing evenly. Use a spatula to smooth the tops. Run your clean finger around the edge of each ramekin to wipe away any excess batter—this prevents uneven rising.

8. 8

   Place the baking sheet in the preheated 400°F oven and bake for 16–20 minutes, until the soufflés are puffed and golden brown on top with a slight jiggle in the center. The tops should be set but the interiors still have a faint wobble when gently shaken.

9. 9

   Remove the soufflés from the oven and immediately dust the tops with confectioners sugar. Garnish each with a few fresh raspberries.

10. 10

    Serve immediately while still warm and puffy, as soufflés will begin to deflate shortly after removal from the oven.