I start by preheating my oven to 350°F (175°C) so it's fully hot by the time my batter is ready. While it warms, I lightly coat a 12-count mini donut pan with nonstick spray. This little step keeps the donuts from sticking and makes cleanup so much easier later.
In a medium bowl, I whisk together the flour, baking powder, instant vanilla pudding mix, and salt. Whisking these dry ingredients first helps distribute the leavening evenly, so every donut rises the same. I set this bowl aside while I work on the wet mixture.
In a separate large bowl, I whisk the sugar, eggs, buttermilk, melted butter, and vanilla paste until the mixture looks smooth and glossy. This is one of my favorite easy doughnut recipe without butter tricks using just a couple tablespoons keeps things light while buttermilk does the heavy lifting for moisture.
I gradually fold the dry ingredients into the wet mixture, stirring gently just until combined overmixing makes for tough donuts, so I stop as soon as I don't see streaks of flour. Then I scoop the batter into a piping bag or a zip-top bag with the corner snipped off, and pipe it into each donut cavity until it's about three-quarters full.
I slide the pan into the oven and bake for 8 to 10 minutes, checking that the donuts spring back lightly when I press them. Baking instead of frying is what makes this one of the easiest donut recipe options out there, since there's no hot oil to manage. I let them rest in the pan for two minutes before moving on.
Once the donuts have set a bit, I transfer them to a wire rack to finish cooling all the way. This step matters more than people think warm donuts will melt the icing right off instead of holding a nice glossy coat.
While the donuts cool, I whisk powdered sugar, vanilla paste, and milk in a bowl until smooth. If it looks too thin, I add a touch more powdered sugar; if it's too thick to dip easily, a splash of more milk fixes it right up.
Once the donuts are fully cool, I dip the tops into the icing, letting the extra drip back into the bowl before setting them frosting-side up on the rack. While the icing is still wet, I press two candy eyes onto each one so they stick in place, then let everything set for a few minutes before serving.