Blanch the beans in lightly salted boiling water for 1 minute, then drain and refresh under cold water. Dry well.
Cut the sausage into slices about 1/4 inch thick. Heat the oil in a frying pan, add the garlic and fry gently for 2-3 mins, until softened and discard. Increase the heat, add the sliced chorizo and stir fry for 2-3 minutes until it is golden and has released some of its oil.
Stir in the beans and cook for a further 2-3 minutes, then add the herbs, squeeze over the lemon juice and season to taste with salt and pepper. Serve warm with crusty bread,.