Ugh, food processor. I shudder at the memory of cleaning up afterwards. I found poppyseeds in my hair.
It didn't do the greatest job, either. It made a paste, kind of, but there were plenty of almost-whole poppyseeds hangin' around. My dad told me the next day that his mother used to grind them through a hand-cranked meat grinder (?!) which I somehow kind of doubt, but I actually own that particular ancient grinder now so maybe if there's a "next time," I'll give it a shot.
I kind of pieced together the recipe from several sources, but it went like this:
Just shy of a pound of poppyseeds (around 400g)
1 tbsp honey
1 1/2 cups icing sugar
6 eggs, separated
1/4 cup ground almonds
A couple tbsp fresh orange juice, plus zest
Butter and sugar, for the pan
Pour boiling water over poppyseeds to cover. Let stand at least half an hour or until soft enough to "pop" when pinched. Overnight would probably be great. Drain well and grind with 1 tbsp honey. Stir in almonds, a tablespoon or two of juice and zest.
Butter a 11" springform and coat with granulated sugar. Set aside. Preheat oven to 375F.
Whisk egg yolks with sugar until smooth. Add poppyseed mixture in stages, combining well after each addition.
Whip egg whites until foamy; add 1 - 1 1/2 tbsp orange juice (or lemon juice, or just use cream of tartar) and whip again until soft peaks; add 1-2 tbsp sugar (until barely sweet) and whip until firm but not dry.
Lighten poppyseed mixture with a scoop of meringue; then gently fold in remaining meringue. Pour mixture into prepared pan; bake for about an hour. Top will be browned and slightly cracked.
The next day, I halved it and filled it with buttercream, then glazed the top. The whole thing disappeared on Christmas Eve. Of course, I think I had three helpings, but shh.