Yemas de Santa Teresa

Yemas de Santa Teresa take their name from Saint Teresa of Avila (1515-1582), the Carmelite reformer; the recipe is by tradition attributed to nuns of an Avila convent, though its true origin is uncertain. The name and commercial fame date to 1860, when the Avila confectioner Isabelo Sanchez of the pastry shop La Flor de Castilla (then La Dulce Avilesa) sold them as 'Yemas de Santa Teresa'. The dish's underlying technique — dense egg-yolk pastes set with sugar — is older, descending from medieval Andalusian sweets and ultimately the sugar-and-yolk traditions of Moorish Spain. Spanish convents preserved many such recipes because nearby wineries used egg whites for clarification and gave the surplus yolks to the nuns.

Named for Saint Teresa of Avila (1515–1582); convents stockpiled these because nearby wineries used egg whites for clarification and gave the surplus yolks to the nuns. Two thresholds: syrup at soft-thread (~110°C) and yolk-mass held at 75°C — push past either and you get grainy or curdled.

A bright yellow ball the size of a marble, crystal sugar coat giving way to a dense, almost fudge-like paste that melts into pure cooked-yolk richness — closer to thick custard set firm than to candy. One is enough next to a coffee. Too soft and the yolks were undercooked; too grainy and the syrup went past soft-thread; bitter at the back means the pan scorched and the whole batch took the burn.

Two thresholds matter. First the syrup must hit soft-thread (~110°C) and not pass it — beyond that it crystallizes and the yemas turn grainy. Second the yolk-syrup mass must cook to ~75°C but not above — yolk proteins set fully there but won't curdle if held there briefly. The constant stirring at low heat is what keeps the texture smooth; lift the spoon and the bottom scorches in seconds. Egg whites are not used because they would turn the paste rubbery.