For the lime curd, whisk lime zest, juice, sugar, and eggs in a medium sauce pan. Cook over medium-low heat, whisking constantly, until mixture thickens to the consistency of loose pudding, about 10 minutes. Remove from heat and whisk in butter, a few slices at a time, until completely melted and smooth. Pour mixture through a fine strainer into a clean bowl and let it cool to room temperature. Place plastic wrap directly on the surface of the lime curd and refrigerate until well chilled, at least two hours.

To prepare the graham cracker cups, combine the butter, brown sugar, and honey in the bowl of a standing electric mixer fitted with the paddle attachment. Beat until fluffy, about 5 minutes.

Whisk flours, salt, and cinnamon in a small bowl to combine. Add the dry ingredients to the butter mixture in three additions, beating until just combined after each addition. Beat the mixture for about one minute after the final addition to ensure even distribution of ingredients. It's okay if the dough looks a bit crumbly. Gather the dough together and press it into a flat disk. Wrap tightly with plastic and refrigerate for about 30 minutes before rolling (if you refrigerate it for much longer, let it soften at room temperature a bit before continuing).

Lightly grease 18 cups in two standard-sized muffin tins. Unwrap the dough and place it between two large sheets of parchment paper. Roll the dough to a thickness of about 1/8 inch. Peel away the top layer of paper and dust the dough lightly with flour. Replace the paper, flip the dough over, and remove the other piece of parchment paper. Using a 3¾-to 4-inch flower-shaped cookie cutter, stamp out as many flowers as possible.

Gently transfer the dough to muffin tins, tucking each flower into one of the cups. If you have difficulty transferring the flowers, you may need to dust the dough with more flour before cutting the shapes. Gather scraps, re-roll, and cut flowers as many times as needed until you have prepared 18 cups.

With a toothpick or sharp skewer, prick holes in the dough around the bottom edge of the cup, about 1/8 to 1/4 inch apart, adding a few holes in the center as well.

Transfer muffin tins to the refrigerator for at least 15 minutes before placing them in an oven preheated to 350° F. Bake for 10 to 12 minutes, until just set, shifting the baking sheets halfway through for even baking. Remove from oven and let cool in the muffin pans for about 5 minutes. Loosen the cups with a thin metal spatula before allowing them to cool completely in the muffin pans.

Once the cups have cooled completely, pipe or spoon prepared lime curd into them and chill uncovered until ready to serve.

Just before serving, beat heavy cream with confectioners’ sugar and vanilla until it just holds stiff peaks. Pipe or spoon the whipped cream on top of each tart. Garnish with lime wedges, if desired.