Using a tablespoon or so of the almond oil, lightly oil the bottom of an 8-inch cake pan. Line with a round of parchment, lightly oil this with another tablespoon or so of the oil and then dust with flour shaking out the excess.
With an electric mixer beat the butter, remaining oil (you should have around 1/3 cup) and sugar together until fluffy, about 4 minutes. Add the almond paste, lemon zest and juice and beat until smooth. Beat in the eggs 1 at a time making sure each is fully incorporated before adding the next. Fold in the flour and baking powder.
Pour batter in prepared pan and bake in a preheated 325 degree oven for 50 to 55 minutes or until a cake tester comes out nearly clean. While cake is baking, combine glaze ingredients in a small saucepan and over moderate heat stir until sugar is dissolved. Remove from heat and set aside to cool.
When cake is done, cool on a rack for 15 minutes and then turn cake out to cool completely. Transfer cake, topside up to a plate and brush glaze over the top so that it soaks in completely. Cake can be made up to 2 days ahead. Wrap in plastic and store at room temperature.
Recipe courtesy of John Ash