- Preheat oven to 325 degrees. Put heavy cream into saucepan and scald cream over medium-high heat. Remove from heat.
- Whisk together eggs, yolks, and 2¼ cups maple syrup until combined. Slowly, start pouring hot cream into egg mixture, continuing to whisk until smooth and homogenous. Pour mixture through a fine-mesh sieve into a clean bowl.
- Pour custard into 4 4-ounce ramekins, leaving about ⅛ inch at top. Place filled ramekins into baking dish and add enough hot water to submerge ramekins halfway. Cover pan in foil and carefully place in oven. Bake about 40 minutes or until mostly set (when done, custard should shake like jello).
- Remove from oven and remove foil. Let cool, then remove from water bath. Place in refrigerator for about 4 hours.
- Right before serving, place 1 cup mixture of toasted walnuts and lardons in a frying pan with 2 tablespoons maple syrup. Cook 3–4 minutes over medium heat, just until syrup begins to boil and coats nuts. Remove from heat.
- Apply thin, even layer of granulated sugar in the raw to surface of each custard. Add walnuts and lardons evenly to each. Using a blowtorch, melt sugar until it’s light brown and has formed a crisp top. Rest crème brûlée until surface has cooled, about 5 minutes.