In a medium bowl, whisk together the two flours and yeast. Form a small well in the center of the flour.
In a measuring cup, heat the milk in the microwave for about 50 seconds. The temperature should feel like a hot bath.
Pour in the milk and stir. Cover with cling film and let rise for 40 minutes.
Once the dough has risen, it is time to enrich the batter. Add in the melted butter, salt, and the egg yolk. Stir to combine.
In a separate bowl, whisk the egg white until stiff but not dry. Gently fold the egg white into the batter. Cover and let rise for another 30 minutes.
Heat a non-stick skillet or flat griddle to medium heat, do not grease the pan. Pour the batter slowly to form miniature pancakes, about the size of a toonie/poker chip.
Fry the pancakes for approx. 60 seconds on each side and flip once you see little bubbles popping at the surface of the pancake. Aim to have a even light golden colour on the blinis. Serve the blinis room temperature or slightly chilled.
To serve, open the caviar tin and place in a serving dish with ice. Spread a small amount of clotted cream on a blini, then caviar, and garnish with chives.