Petite Mascarpone Cheesecakes in jelly jars topped with sweet, tangy Key Lime Curd are an ideal 'just right' dessert for parties, as part of a dessert bar of when a little something sweet is all you want.
Note on Total Recipe Time: the bulk of the total recipe time is for the chilling of the key lime curd which is 8 hours. This may be made in two sessions; one for the key lime curd and one for the cheesecakes.
Mix sugar, cornstarch with lime juices in a saucepan with lid. Whisk in eggs. Heat on medium to medium high until boiling, stirring constantly.
Remove from heat and mix in butter and lime zest. Place plastic wrap directly on the custard, cutting holes for venting (a bamboo skewer works great for this). Cover refrigerate at least 8 hours. Unused curd maybe be stored in the refrigerator, sealed, for two weeks or stored in the freezer for up to six months.