Treat size names as regional
A “large” egg is not the same weight in every country. For precise baking, weigh the edible egg or use the recipe author’s stated grams. Beat several eggs together before weighing a partial amount rather than trying to divide a white and yolk unevenly.
Use temperature deliberately
Room-temperature eggs combine more readily with softened butter and can support greater foam volume. Cold eggs are easier to separate. Warm whole eggs safely in their shells in lukewarm water for a few minutes rather than leaving them out for long periods.
Add eggs without breaking the mixture
In a creamed batter, add beaten egg gradually so the water can disperse through the fat-rich mixture. If it starts to look curdled, pause and add a little of the recipe’s flour. For foams, use a clean grease-free bowl and stop at the peak stage the recipe specifies.