A cured phenolic resin may be prepared by reacting (1) an esterified phenolic compound containing one or more phenolic hydroxyl groups and/or one or more esterified phenolic hydroxyl groups and further containing one or more esterified methylol groups ortho and/or para to the (esterified) phenolic hydroxyl group and (2) a phenolic resole resin in the presence of a base and water and/or other polar solvent. This technique may be used in the production of phenolic-based adhesives, foundry moulding compositions, surface coatings, foams and proppants.