Add the cottage cheese, eggs, honey, avocado oil, oat milk, lemon zest, lemon juice, and vanilla to a blender. Blend until completely smooth, about 30 seconds. Set aside.
In a large mixing bowl, whisk together the oat flour, baking powder, baking soda, and salt until evenly combined.
Pour the blended wet mixture into the large bowl with the dry ingredients and fold together gently with a rubber spatula until just combined. Stop as soon as no dry streaks remain -- see Tips on why overmixing matters here.
Gently fold the blueberries into the batter immediately after combining the dry ingredients. If using frozen, add straight from the freezer -- do not thaw first. Folding them in before the rest (rather than after) keeps the batter undisturbed during the full rest window, which means better lift and taller pancakes.
Once the blueberries are folded in, leave the batter completely alone. The oat flour absorbs the liquid, the batter thickens, and the leavening builds -- all of which means taller, fluffier pancakes. Rest the batter for 8-10 minutes. Do not stir, scoop, or disturb it during this window.
Set a nonstick skillet or griddle and preheat over medium-low heat while the batter rests. You want the pan fully, evenly hot before the first scoop goes in -- a properly preheated pan is what closes the gap between your first pancake and your last.
Grease the pan lightly with butter, ghee, or avocado oil. Scoop batter using a heaping ¼ cup measure for consistent sizing. Cook undisturbed for 2½ to 3 minutes until the edges look fully set and the underside is deep golden brown. Flip carefully and cook 2 minutes more.