Egg tempera painting is made by mixing egg yolk, pigments, and water. The traditional support is a panel prepared with a traditional gesso ground*.

This technique does not allow for impasto: tempera is built up slowly, stroke by stroke, giving the painter the sensation of doing embroidery. Once dry, the paint film is matte, hard, and permanent, without yellowing, which distinguishes it from oil painting.

* Traditional gesso is a mixture of rabbit skin glue and chalk (gesso means "chalk" in Italian). It is crucial to distinguish it from commercial acrylic gesso, which is a polymer with very different absorption and adhesion properties. Acrylic gesso dries within 30 minutes, while traditional gesso requires two weeks of drying time, followed by thorough sanding. This difference explains the frequent use of acrylic gesso as a primer for oil painting, even if this practice remains questionable.