In a mixing bowl, whisk together the egg and milk until well combined. Gradually add in the flour, baking powder, and sparkling water. Mix until just combined, being careful not to overmix.
Place your non-stick frying pan over medium heat. Allow it to preheat for a few minutes while you prepare the brie cream.
In a small saucepan over low heat, combine the brie cheese and cooking cream. Stir continuously until the brie has melted and the mixture is smooth and creamy. Remove from heat and set aside.
Once the pan is hot, pour a ladleful of batter onto the pan. Cook for 2-3 minutes, or until bubbles form on the surface and the edges look set. Carefully flip the pancake and cook for an additional 1-2 minutes until golden brown.
While the pancakes are cooking, place the walnuts in a dry skillet over medium heat. Toast them for 3-4 minutes, stirring frequently, until fragrant and lightly browned. Remove from heat and chop coarsely.
Stack the pancakes on a plate, generously drizzle with the brie cream, and then finish with a drizzle of honey. Sprinkle the toasted walnuts on top for that perfect crunch.