Day 1

1. Prepare the batter. Heat the milk, butter, pepper, and cardamom in a small saucepan over medium heat until it reaches 150F/65C, and the butter melts. Remove from the heat and let cool to 100F/35C.
2. Whisk in the egg yolks, rum, and sugar, gently until combined. Do not whisk the batter aggressively; it will introduce too much air into the liquid.
3. Add the flour and salt and whisk gently until combined. Do not whisk the batter aggressively; it will introduce too much air into the liquid. Strain the liquid through a fine mesh sieve into a container. Place a piece of plastic wrap over the surface of the batter and leave it in the refrigerator covered for 48 hours.

Day 3

Season the Molds

1. Preheat the oven to 450F/230C.
2. Place a few sheets of old newspapers on a baking sheet or the kitchen counter. 
3. Set up a boiling water bath to melt the beeswax; alternatively, melt the wax in the microwave:  Place the beeswax pellets in a small heat-proof jar and add 1/2 cup of the beeswax pellets to the jar. Make a thick ring with aluminum foil and place it at the bottom of a medium saucepan. Place the jar with the beeswax pellets over the ring. Fill the saucepan with enough boiling water to the height of the beeswax in the jar. Heat the water over medium heat until the wax is completely melted.
4. Line a baking sheet with foil. Place the cannelé molds in the pan, open side facing upwards, and leave in the oven for 15 minutes to preheat. Work with one mold at a time. Once hot, pour a little (about a Tbsp or less) of the hot melted wax into each mold. Carefully rotate the mold to help the hot wax coat the inside of the mold, and then flip and place it over the newspaper to get rid of any excess wax. If you’re careful, you can also pour the extra hot wax into another mold and reuse it. The layer of wax inside the mold should be very thin. Flip over and return to the baking sheet with the aluminum foil. Season all the molds and return the sheet to the oven to preheat the molds for 15 minutes. 

Preparing the Cannelés

1. While the cannelé molds are being seasoned, leave the batter out at room temperature for 30 minutes. The liquid will appear thick; stir gently with a silicone spatula to disperse the settled flour evenly. 
2.  Fill each hot mold with enough batter leaving about 1/4 in/6 mm of dead space at the top. Bake in the preheated oven for 30 minutes. 
3. Reduce the heat to 350F/180C. Rotate the baking sheet halfway through and bake for 1 hour to 1 hour 10 minutes, until the tops appear caramelized. The tops should be a dark caramel brown but not black. Watch them bake carefully during the last 15 to 20 minutes, as they can easily overcook and burn. The pastry will rise to the baking and quickly shrink back on cooling. Once baked, remove the baking sheet with the molds from the oven and let them cool for 5 minutes in the molds. Flip the molds over a baking sheet lined with a wire rack and tap gently to release the cannelés. Let them cool completely to room temperature before serving. They taste best the day they’re made, especially in the first one to two hours. Leftovers can be stored in an airtight container for up to 4 days at room temperature or a week in the refrigerator.