1) In a small bowl combine the buckwheat flour, half of the gluten free flour, the yeast, sugar and warm water; stir until blended. Cover tightly with plastic wrap and let stand in a warm place until doubled in volume, 1 to 1 1/2 hours.
2) In a small saucepan over medium heat, scald the milk by cooking it to just under a boil. Let cool to room temperature and set aside.
3) In a large bowl, whisk together the egg yolks and salt until light in texture and colour, then gradually whisk in the butter until smooth.
4) Stir in the scalded milk and then stir in the remaining flour until smooth.
5) Fold in the risen batter mixture and mix until smooth. Cover tightly with plastic wrap and let stand in a warm place to rise for 30 to 40 minutes.
6) In a large mixing bowl whisk the egg whites until stiff peaks form.
7) Using a spatula, gently fold the egg whites into the batter and let stand for 10 to 12 minutes.
8) In a large non-stick frying pan over medium heat, warm just enough oil to coat the bottom of the pan.
9) Using a dessert spoon drop the batter onto the pan (1 dsp. of batter will make a bite sized blini).
10) Cook until golden, 2 to 3 minutes per side, making sure not to overcrowd the pan.
11) Makes 50 – 60 blinis