Preheat the oven to 350°F.

Grease an 8-inch round cake pan.

Beat the yolks with half the sugar in a large bowl until light yellow.

Beat the egg whites until they form stiff peaks. Fold in remaining sugar. Fold egg whites into the beaten yolks.

Sift together the matzo meal, ground almonds, grated orange zest, and cinnamon, then add to the eggs, a tablespoon at a time, alternating with the orange juice. Fold gently to keep the mixture fluffy.

Pour batter into prepared pan and top with the almond halves.

Bake for 1 hour, or until golden brown.

Let cool for 10 minutes, then remove from pan and let cool completely on a wire rack.