Preheat the oven to 170°C (150 fan) | 325°F | gas 3 and grease and line two baking trays with parchment paper.
In a mixing bowl, cream the margarine and sugar until pale and fluffy using a handheld electric whisk. Beat in the flour, bicarbonate of soda and vanilla extract and knead the dough lightly for 5 minutes.
Roll the dough out on a lightly floured surface to 1 cm thickness and cut half of the dough into round biscuit shapes using a 5 cm round cookie cutter. Use a smiley-face cookie cutter to cut shapes out of the rest of the dough. Arrange on the baking trays spaced apart.
Bake for 15-20 minutes and let them cool on the baking tray for a few minutes before moving to a wire rack to cool completely.
Once cool, spread the plain round cookies with apricot jam. Liberally dust the smiley-face cookies with the icing sugar. Position on top of the jam to complete the biscuits.