Preheat the oven to 180ºC/350ºF/gas 4. Grease two large baking trays with a little margarine and line with greaseproof paper.
In a bowl, beat the margarine, peanut butter and sugar for around 5 minutes, or until light and fluffy. Beat the eggs in a separate bowl, then fold into the mixture with the flour and ground almonds. Roughly chop and fold through the chocolate.
Place heaped teaspoons of the mixture onto the prepared trays, leaving a rough 4cm gap between each. Lightly pat the mixture to flatten slightly, then pop in the hot oven for 12 to 15 minutes, or until golden. Leave to cool for 5 minutes, before transferring to a wire rack to cool completely. Serve with a glass of cold milk or a nice cup of tea.