Preheat oven to 175C. Grease and line a 23cm cake pan.
Beat the sugar and egg well together in a large bowl.
Beat in cooled, melted butter until all combined. (If the butter is too hot it will cook the egg.)
Stir in almond extract, orange zest and almond meal, then add flour, baking powder and salt, stirring until just combined.
Pour into prepared cake pan and sprinkle top evenly with the flaked almonds.
Bake for 40 minutes, or until a skewer inserted in the middle comes out clean.
Cool in pan for 10 minutes, then run a knife around the cake to loosen it. Cool on a cake rack.