3/4 cup milk (any kind; alternatively, you can use 1 cup buttermilk and omit the Greek yogurt)
1 tsp vanilla (optional)
2 tbsp butter, melted, plus more for the pan
For the blackberry syrup, combine blackberries and sugar in a small pot over medium heat. Simmer, stirring continuously and mashing the larger berries, for at least 5 minutes, or until sugar has melted, berries have released their juice, and the mixture forms a thick syrup. When syrup has thickened to where lines remain in the pot when stirred, stir in the goat cheese until dissolved. Remove from heat and set aside. (Note: You can strain the pulp out if you want a smooth syrup — I ended up using both the pulp and syrup on my pancakes.)
For the pancakes, whisk together the cornmeal, flour, sugar, baking powder, baking soda, and salt in a medium bowl. In a separate bowl, whisk together the Greek yogurt, milk, egg yolk, melted butter, and vanilla. Note that you should take care that your other ingredients aren’t cold when you mix in the butter, or else it will re-solidify. It can be cool, just not refrigerator-cold. (If you forget and have it solidify — as has happened to me — just pop it in the microwave for a few seconds and it should be fine.)
Add the dry ingredients to the wet and mix gently until just incorporated and small lumps remain.
In a small bowl or cup, whip the egg white with an electric beater or a very strong arm until it reaches medium peaks. Fold the egg white very gently into the pancake batter — it does not have to be fully incorporated.
Heat a pat of butter in a cast-iron skillet over medium-low heat. When a drop of water sizzles in the pan, you’re ready to cook. Using a 1/4-cup measuring cup, drop batter onto the skillet (you may need to spread it a bit with your cup to form a circle). When bubbles pop on the pancake and leave a momentary hole, flip the pancake to cook the other side. Let cook for 1-2 more minutes, then remove and set aside. Repeat until batter is all gone.