Heat your oven to 180°C/160°C Fan/Gas mark4/355°F and set a shelf in the middle.
Grease your cake tin with butter and then line the base with a circle of greaseproof (parchment) paper.
Sift together your flour, baking powder and salt into a mixing bowl and then stir in your ground almonds.
If using a hand mixer fit the beaters (not the whisk) and if using a stand mixer fit the paddle attachment. Starting on a low setting begin to beat your eggs and caster (superfine) sugar together for 60 seconds.
Wipe the bowl down with your spatula, to ensure all ingredients are mixed in, then turn the speed up to medium-high and continue to beat for another 2 minutes. By this time the mixture should be pale yellow in colour with little bubbles popping up to the surface.
Add your oil, orange zest and almond extract to your eggs and sugar mixture and beat in on a medium setting a few times until just incorporated.
Tip in your sifted flour mixture and either fold in with a large metal spoon or beat on the lowest setting until just mixed in. Don't overmix otherwise your cake will be rubbery and chewy.
Pour into your prepared baking tin and place on the centre shelf. Bake for 35-40 minutes until golden all over and a skewer inserted into the centre comes out clean.
Run a blunt knife around the edges of the cake to ensure it has not stuck to the tin and then leave to cool in the tin for 5-10 minutes before inverting onto a cooling rack.
Whilst your cake is still hot add the apricot jam, this will allow the jam to sink into the top layer of the cake whilst both are still hot and soft.