If planning on serving all pancakes at once, set wire rack in rimmed baking sheet and heat oven to 200 degrees. Cut 2 tablespoons butter into ½-tablespoon pieces and set aside. Whisk flour, milk powder, sugar, baking powder, baking soda, and salt together in medium bowl. Whisk buttermilk, egg, and melted butter together in second medium bowl (it's OK if butter forms clumps). Make well in center of flour mixture and add buttermilk mixture; whisk until just combined (a few lumps should remain). Fold in blueberries.

Heat oil in 12-inch nonstick skillet over medium-low heat until shimmering. Using paper towels, carefully wipe out oil, leaving thin film on bottom and sides of skillet. Drop 1 tablespoon batter in center of skillet. If pancake is pale golden brown after 1 minute, skillet is ready. If it is too light or too dark, adjust heat accordingly. Discard pancake.

Melt ½ tablespoon butter in now-empty skillet and use spatula to spread over surface. When butter is sizzling, use ⅓-cup dry measuring cup or slightly mounded 2-ounce (#16) portion scoop to portion batter into skillet in 3 places. Using back of cups or scoop, gently spread each portion into 4½-inch round. Cook until edges are set and first side is deep golden brown (coloring will not be even), 2 to 3 minutes. Using thin, wide spatula, flip pancakes and continue to cook until bottoms are just set, about 1 minute longer. Gently slide pancakes around skillet to collect butter. Cook until second sides are deep golden brown, 1 to 1½ minutes. Serve pancakes immediately, or transfer to prepared wire rack and place in oven to keep warm. Repeat with remaining butter and batter in 3 batches.