Place the bread in an oven at 150°C for 20 minutes until completely dried. When cool, place in a plastic bag and crush until you have breadcrumbs.
Part boil the happy eggs by putting them in gently boiling water for 4 minutes (if the eggs are at room temperature), or 6 minutes (if they are from the fridge).
Place the eggs in cold water for a few minutes, gently tapping them to crack the shell. The shell will now peel off easily
Take the sausages and slice off the skins. Remove the meat, dividing it into 4. Gently squeeze and shape the sausage meat evenly around four of the happy eggs.
Crack the remaining egg into a bowl and whisk with a fork. Put the flour in a bowl and the breadcrumbs in another bowl.
Dip each of the scotch eggs in the whisked egg, then roll them in the flour, then the breadcrumbs.
Place on a baking tray and cook in a preheated oven at 160°C for 30 minutes.
See more Christmas recipes
Haven't got time to cook this from scratch?
Try our ready-made version - Tesco bitesize mini savoury eggs.
If serving vulnerable groups, elderly people, toddlers, pregnant women and people who are unwell, cook eggs until the whites and yolks are solid.
For top tips on protecting you and your family when preparing raw meat and poultry, visit Food Safety in the Home.