Grease 12 muffin cups and set aside. (I have an awesome tin that holds 12 at once, I love it. Got it at Goodwill for $4! I never, ever use paper liners.)
In a medium bowl, combine 1 3/4 cups flour, 1/3 cup sugar, 2 teaspoons baking powder, and 1/4 teaspoon salt. Stir to combine. Make a deep well in the center and then set the bowl aside.
In another bowl, combine one egg (I always use Eggbeaters), 3/4 cup milk, and 1/4 cup cooking oil. Stir to combine.
Then, pour the wet ingredients into the dry ones, all at once. Stir until everything is just moistened. The mixture will be lumpy, this is ok!
Fold in one cup blueberries.
Spoon batter into muffin tins until 2/3 full. (I have an awesome scoop that just zipipzip puts the exact amount in.) Bake at 400 degrees for 20 minutes. The muffins will get a bit golden on top, but if they have intense color, that is TOO done and they will be crunchy and you don't want that. Let the muffins cool, in the tin, for five minutes. (I always want to skip this step but that is a mistake. They need the cooling time to set up a bit before they come out of the tin.)
Remove from tin and eat! I keep them in an airtight glass container in the fridge, eating one a day, and they keep fine.
A word on blueberries...fresh blueberries work best. Be sure you thoroughly wash them before eating though as they are one of the worst foods in regard to pesticides. I usually buy a container, wash the fruit, and then freeze it so I can pull out what I need. Fresh-frozen also work well.
If you buy frozen blueberries at the grocery store, they will work in this recipe. But every time I've ever done this, the berries leak their color into the batter and it turns everything a really unappetizing color of grey. They still taste great, they just look...not great.
My fave way to eat these is to plunk one down into a shallow bowl and cut it into pieces. Then, I spoon plain greek yogurt on top. Add sliced almonds and a couple of squirts of really good honey. Sometimes I slice a banana on top too, but usually not. So good and so easy, and it makes a really great breakfast!