Beat softened butter, brown sugar, and honey in a stand mixer until creamy.
Add flour and salt; mix until the texture resembles fine sand.
Add the beaten egg and mix on low just until dough forms (don’t overmix).
Divide dough into two uneven portions (⅔ and ⅓); flatten into discs.
Roll each disc between parchment paper to ⅛" thick and refrigerate both on baking sheets for 30+ minutes.
Preheat oven to 350°F (175°C).
From the larger dough sheet, cut out 28 circles using a 2¾" round cutter.
Place rounds in muffin tin wells and press to form shells (use fingers or flat tool).
Chill muffin tin in the freezer for 10 minutes, then bake bases for 10–12 minutes until golden.
From the smaller dough sheet, cut 28 circles with a 1¾" cutter.
Stamp a 1" heart in the center of each and mark 12 small clock-like lines around it.
Chill these tops in the freezer for 10 minutes, then bake for 10–11 minutes until golden. Cool completely.
Spoon or pipe 1 teaspoon of Nutella (about 12–14g) into each cooled cookie base.
Gently press the decorated top onto the Nutella, twisting slightly to set. The filling should peek out around the edges.