This filling works very well between cake layers, and also as a somewhat substantial sauce. It is reminiscent of the lemon part of lemon meringue pie. The flavor is somewhat tart, not overly sweet. You may alter the sweetness to your preference.
| ½ | cup | White Sugar |
| 1 | pinch | SaltCan be omitted but definitely contributes to the taste |
| 4 | tbsp | CornstarchMeasure this by putting the spoon into the box, filling the spoon and then pressing the spoon against the side of the box so that the cornstarch is pretty well packed in. |
| ¾ | cup | Water |
| 1½ | tsp | Lemon ZestOr the amount grated from at least one lemon. |
| ¼ | cup | Lemon JuicePreferably, freshly squeezed. |
| 1 | tbsp | Unsalted Butter |
| 1 | Begin by collecting the ingredients. Grate the lemon zest and squeeze the lemon juice taking care to remove the seeds. |
| 2 | In a small heavy-bottomed pot combine the sugar, cornstarch, and salt. Mix well. |
| 3 | If possible, have near the stove the zest and juice, which may be combined, as well as the tablespoon of butter. |
| 4 | Add water to the cornstarch mixture and mix well until smooth (this will take only a few minutes). |
| 5 | Heat the mixture over medium-low heat, stirring constantly, until the mixture becomes somewhat transluscent and thickened. Depending on the intensity of heat, this takes just five minutes or so. Continue stirring and cooking over low heat so that the mixture is still bubbling gently. Although the mixture has thickened, further cooking is needed so that the cornstarch loses its raw taste. This takes just two minutes or so. At this point the mixture is quite thick. Remember, you are going to add both butter and lemon juice. Also, you want this to have good body in order to use it for a cake filling. |
| 6 | Remove from the heat. Add the butter and mix until the butter is melted; this helps to cool the mixture. Then add the lemon juice and zest and continue to mix until well-blended. |
| 7 | If you like, remove the mixture to a bowl or container for storing. Every few minutes, stir the mixture to release steam and also prevent a skin from forming on the top. After fifteen minutes, you may cover the mixture with plastic wrap with a few pokes to allow for continued evaporation. |
| 8 | This completes the recipe. If, when you're ready to fill the cake, the mixture seems too thick, add just a teaspoon or so of warm water and mix well. Whatever your "political stripe," be conservative here. |
| 9 | Should you prefer a creamier filling, use skim or regular milk for the liquid. |