If you’re the sort of person who loves big cookies and hates sharing, you’ve come to the right corner of the internet. Over the last couple of years, I’ve posted three “One Big” cookie recipes: chocolate chip, chocolate M&M, and snickerdoodle. Each one is a super small-batch version of a classic that yields exactly one big cookie for one hungry person (or two people, if you’re nicer than me).You’d think after posting three single-serve cookie recipes on this site, I’d be able to churn out a new one in my sleep, but you’d be wrong. This lone oatmeal cookie? It took 27 tries. Twenty. Seven. That’s the highest number of concentrated tests I’ve ever done for one recipe.

Despite the fact that all my single-serve cookies start with similar basic ingredients and proportions, formulating them is always an adventure. The simplest recipes always seem to be the most challenging for me. Everything has to fit together just right or it’s not worth the effort. It’s like my hero, Martin Scorsese said, “There’s no such thing as simple. Simple is hard.”The good news about this recipe, though, is that while it was hard to get it exactly right, it is very simple. Oh, and it makes one kickass, golden brown, chewy as all get-out oatmeal cookie. Oh my goodness, it is so good. Trust me—I’ve bitten into 27 cookies to get this one exactly right. Quality control, you know?Like all my One Big cookies, the ingredients here are measured by the spoonful rather than in cups. Oats replace some of the usual flour (duh) and I’ve added a hint of cinnamon for that classic oatmeal cookie flavor. You’ll notice that there’s no egg in this dough, as I prefer to use water for such a tiny portion. As a bonus, no egg means this recipe can easily be made vegan! Just swap vegan butter for the dairy butter ☺️ The big secrets to golden, chewy oatmeal cookie success? Before baking, press down on the dough ball to form a puck. This encourages a consistent shape, texture and browning pattern. Nothing terrible will happen if you don’t press down your dough ball, but your cookie likely won’t look like mine.

Also, let the dough rest for five minutes at room temperature before baking. This dough is sticky and might over-spread a bit if baked immediately after mixing. By letting it “set up” for five minutes before baking, we’re ensuring thicker, chewier results.As far as mix-ins go, use whatever you like. I went for classic oatmeal raisin for photos, but rest assured that I made a few with chocolate chips, too. Nothing but the most thorough cookie testing here at E2 Bakes.Have a good weekend, y’all. Make yourself a cookie.

One Big Oatmeal Cookie
makes 1 large cookie

1 tablespoon unsalted butter, melted
2 tablespoons light or dark brown sugar, packed
1 teaspoon water (not cold)
1/8 teaspoon pure vanilla extract
2 tablespoons all-purpose flour
2 tablespoons old-fashioned oats
1/8 teaspoon ground cinnamon
1/8 teaspoon baking soda
pinch of Kosher or sea salt

2 tablespoons raisins (or semisweet chocolate chips), plus more for optional topping

Preheat oven to 350F. Line a baking sheet with parchment. Set aside.

In a small bowl, use a fork to whisk together melted butter and brown sugar. Mix in water and vanilla. Add flour, oats, cinnamon, baking soda and salt, and whisk until a dough forms. Use a silicone spatula or spoon to mix/fold in raisins (or chocolate chips).

Use your hands to form dough into a ball and place on parchment. Dot with additional raisins (for aesthetic purposes), if desired. Use the heel of your hand to press down gently on the dough, just so that the dough is a 1-inch thick puck.

Let dough puck rest on the parchment for 5 minutes before baking.

Bake for 13-14 minutes or until edges have darkened to a golden brown color and center is still a bit pale.

Let cookie cool on the pan for 5-7 minutes before using a spatula to remove it to a plate. Enjoy warm or at room temperature.