In a stand mixer, beat butter with sugar, salt, and cardamom. Add the orange zest by zesting the entire orange over the bowl—this allows the zest and any oils to be incorporated into the butter. Beat the butter, scraping the sides as needed, until whipped smooth, and malleable— 3-4 minutes. Set aside.
Roll each sheet of puff pastry into a 12’’ square—I recommend doing this on a sheet of parchment or a lightly floured surface.
Spread half the softened butter into a thin even layer onto one sheet.
Place the other sheet on top of the buttered pastry, and roll out about an inch in each direction, so the pastry is about a 13’’ square.
Spread the top of the pastry with the remaining butter and fold in half, lengthwise, once more. Roll out until 16’’ wide.
Using a knife or pizza cutter, divide the dough in half. Divide each half into 4 strips, then 8, then 16.
Take each 1 inch strip and gently pull apart an inch or so and twist tightly. into a spiral. Place on a parchment-lined baking sheet. Once all pieces are twisted, place in the refrigerator for 5 minutes until chilled. Transfer half of the twists to a parchment-lined baking sheet—you’ll need to bake them in two batches so they have enough room to puff. Keep the second batch in the refrigerator until ready to bake.
Brush the twists with the egg wash and sprinkle each with about 1/2 tsp of the remaining sugar. Transfer to the oven for 18-20 minutes, rotating the pan 180 degrees midway through baking. Repeat for the second batch of twists.
Remove from the oven and allow to cool slightly before enjoying with whipped cream.