* Remove the lemon rind with a vegetable peeler, being careful to avoid the white pith, which will impart a bitter flavor.
Pulse almonds with 2 tablespoons of the sugar in a food processor until ground to a fine paste.
Bring milk, cinnamon, lemon rind, vanilla and baking soda to a boil over medium-high heat in a large heavy-bottom saucepan. Reduce heat to medium-low and simmer for 15 to 20 minutes. Strain the lemon rind and cinnamon sticks from the mixture, set aside
In a large bowl, whisk egg yolks, the remaining 1½ cups sugar and ground almonds until thick and pale. Whisking constantly, slowly add the milk to the yolk mixture.
Return mixture to pan and cook over low heat, constantly stirring and scraping the bottom and sides of the pan, until the mixture thickens enough to coat the back of a spoon, 5 to 7 minutes. Set aside to cool completely, about 2 hours.
Milk of the Poppy:
Once you make the rompope and it has cooled, measure volume and add 1 part cognac for every 3 parts rompope. Then add half that amount of glogg. Example: 3 cups rompope + 1 cup cognac + ½ cup of glogg. Glogg is a Scandinavian mulled wine that’s deliciously festive in flavor.
Once cognac and glogg are added, the mixture can stay refrigerated for up to a month.
When serving, grate fresh nutmeg onto the drink as a garnish.