Dissolve the cornstarch in reserved ½ cup of cold milk. Reserve. In a medium saucepan, bring the rest of the milk, evaporated milk, cinnamon stick and cloves to a boil, stirring constantly to avoid scorching. As soon as it starts boiling, lower heat, add the cornstarch and stir vigorously with a wooden spoon until milk thickens. Remove from heat, stir in vanilla and let cool. While milk is cooling, beat the egg yolks for about 4-5 minutes on high speed until they turn a pale yellow color.