This delicious recipe was adapted from Everyday Food magazine, and is a great way to use up some of those lemons and limes.
1/2 cup (1 stick) unsalted butter, room temperature, plus more for pan
1 1/2 cups sugar
1 teaspoon finely grated lemon zest, plus 1 teaspoon fresh lemon juice
1 teaspoon finely grated lime zest, plus 1 teaspoon fresh lime juice
2 large eggs
1 cup all-purpose flour (spooned and leveled)
1/4 teaspoon coarse salt
1 lemon (ends cut off), very thinly sliced and seeded
Preheat oven to 350 degrees F. Lightly butter a 24-cup mini-muffin pan. In a large bowl, using an electric mixer, beat butter, 2/3 cup sugar, and lemon and lime zests on medium speed until light and creamy (not fluffy). Add lemon and lime juices along with eggs and beat to combine, scraping down bowl. With mixer on low, gradually add flour and salt and beat until blended. Divide batter among muffin cups (about 1 tablespoon each). Bake until cakes are golden around edges and a toothpick inserted in center comes out clean, about 15 minutes.
Meanwhile in a small saucepan, combine 2/3 cup water and 2/3 cup sugar; cook over medium, stirring occasionally until sugar dissolves, about 5 minutes. Add lemon slices and rapidly simmer until peel turns translucent and lemon syrup thickens slightly, 5 minutes.
With a toothpick, poke holes all over tops of warm tea cakes in pan. Drizzle 1/2 teaspoon lemon syrup over each cake. Let cakes cool slightly in pan; transfer to a wire rack to cool completely. Spoon lemon slices on top if desired.