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To make the crumb topping, combine the granulated sugar, brown sugar, flour, salt, and butter in a small bowl and toss with a fork until evenly moistened and the mixture forms small clumps. Set aside.
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To make the muffins, preheat the oven to 400°F. Line a 12-cup muffin pan with paper liners. Spray a paper towel with nonstick spray and rub it oven the top of the pan, to grease the part where the muffin top overflows.
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Whisk the flour, baking powder, baking soda, and salt in a large bowl. Whisk the sugar, eggs, melted butter, and oil together in a separate medium bowl. Whisk the yogurt (or buttermilk) and vanilla into the sugar mixture.
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Stir the sugar mixture into the flour mixture until just combined and no streaks of flour remain (the batter will be thick). Gently stir in the blueberries. Using a heaping 1/4-cup dry measuring cup, divide the batter between the muffin cups (they will be very full). Sprinkle the tops with the crumb mixture, pressing gently to adhere.
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Bake the muffins until they are golden brown and a toothpick inserted in the center comes out with a few crumbs attached, 18 to 20 minutes. Cool in the pan for 10 to 15 minutes, until they are set and you can easily remove them without tearing the tops.