Stir nonstop until the mixture boils and thickens, taking care not to let it catch and burn on the base of the pot.
Times, Sunday Times
Once the mixture boils, reduce the heat and simmer for 5 minutes, making sure the liquid doesn't reduce.
Times, Sunday Times
Stir for 4-5 minutes, or until the mixture boils and thickens.
Times, Sunday Times
Some mixtures form azeotropes, where the mixture boils at a lower temperature than either component.
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