Cook the sausages and let them cool slightly.

Separate the egg yolks from the egg whites. Set the yolks aside for now, and beat the egg whites in a clean bowl for about 2 minutes until stiff peaks form. Be careful not to have any trace of yolks in the whites to achieve a firm foam.

In the yolks, add the beer, flour, baking powder, and salt. Mix well.

Once you have a homogeneous mixture, gently fold the egg whites into the yolk mixture using a spatula. Do not use a mixer for this step.

Set the beer batter aside and heat the oil in a frying pan. The amount of oil depends on the size of your pan, but it should be about two-thirds deep.

When the oil is hot, dip a sausage into the beer batter, making sure it is completely coated. Carefully transfer the coated sausage into the hot oil and fry for about 3 minutes on each side, or until it turns golden brown.

Remove the sausages from the oil and place them on paper towels to drain any excess oil. Serve with your favorite side dish and yellow mustard.