Boil whole oranges for 1 hour, changing water twice to remove bitterness, drain, and cool. Blend whole oranges in food processor. Beat eggs honey and cardamom until creamy, and then stir in the orange pulp. Add almond meal mixed with baking powder, the mix will be fairly soft. Pour into baking try suitable for slices and bake at 160 for 20-30 mins check with skewer. Cool before lifting out and cutting.