Preheat oven to 350 degrees. Line a standard 12 cup muffin pan with cupcake liners.
In the bowl of a mixer, preferably fitted with the paddle attachment, beat the butter and sugar together until light and fluffy, about 3 minutes. Add the eggs, one at a time, beating well after each addition.
In a mixing bowl, whisk together the flour, baking powder, and salt.
In another bowl or liquid measuring cup, mix together the buttermilk, lemon zest and juice, and vanilla.
With the mixer on low speed, add half the flour mixture, the buttermilk mixture, then finally the remaining half of the flour. Mix just until combined. With a spatula, scrape the sides and bottom of the mixing bowl to ensure all ingredients are fully combined. Divide the batter equally among the prepared muffin cups. Insert 3 jellybeans into each cupcake.
Bake for 25 – 30 minutes or until the cupcakes are lightly browned and set. Let cool in the pan for 5 minutes, then transfer to a wire rack to finish cooling.
Frosting and decoration:
In the bowl of an electric mixer, preferably fitted with a paddle attachment, beat the butter and cream cheese together until smooth. Turn off the mixer. Sift in the powdered sugar, add the lemon zest and juice, and vanilla. Start with the mixer on low, then gradually increase the speed to high, and beat until smooth. If the frosting starts to look curdled, keep beating until smooth. Put the frosting in the refrigerator for about 30 minutes to firm up.
Frost or pipe the frosting on top of the cooled cupcakes. You can sprinkle a few jellybeans onto the frosting or for a nest, spread a thick layer of frosting on the cupcakes, dip into coconut and nestle 3 jellybeans in the center of each “nest.”
For flowers, place jellybeans in concentric circles, starting at the center, to look like a flower.