Line your tin: Place cupcake cases in a 12-hole muffin tin. This keeps the nests neat and makes them easy to lift out.
Melt the chocolate: Add chocolate, butter, and golden syrup to a microwave-safe bowl.
Heat in 20–30 second bursts, stirring between each, until smooth. Alternatively, melt gently in a heatproof bowl over a pan of simmering water.
Add flavor: Stir in vanilla extract and a small pinch of salt if using. The salt sharpens the chocolate flavor.
Fold in the cornflakes: Tip in the cornflakes and gently fold with a spatula until every flake is coated.
Be careful not to crush them too much—you want that crunch.
Shape the nests: Spoon the mixture into the cupcake cases. Use the back of a spoon to press a shallow well in the center of each to form a nest shape.
Top with eggs: Add 2–3 mini chocolate eggs to each nest while the mixture is still soft so they stick.
Chill: Refrigerate for 45–60 minutes, or until set and firm to the touch.
Serve: Peel away the paper cases and enjoy. They’re best slightly chilled but not rock hard.