Step 1

Preheat oven to 200°. Using an electric mixer on medium-high speed, beat egg whites until foamy, about 1 minute. With mixer running, gradually add granulated sugar. Continue to beat until meringue triples in volume, is shiny, and holds medium-stiff peaks, 8–10 minutes. Add powdered sugar and beat just to blend.

Step 2

Spoon 2 heaping tablespoonfuls of meringue onto a parchment-lined baking sheet; repeat to fill baking sheet, spacing 1" apart. Bake until dry, about 4 hours.

Step 3

DO AHEAD: Meringues can be baked 5 days ahead. Keep airtight at room temperature.

Step 4

Whisk crème fraîche, mascarpone, powdered sugar, and rose water, if using, in a medium bowl.

Step 5

Arrange meringues, crème fraîche mixture, strawberries, and scoops of sorbet in a large bowl. Drizzle with pomegranate molasses and top with pomegranate seeds, sumac, and rose petals, if using.