This is not a fluffy, lavishly adorned, and fancifully frosted cake you indulge in wickedly.

Rather, this is a cake that will stick to your ribs and set you up for a long, arduous day ahead.

Yes, “Blackberry Oatmeal Cake” is far from dessert, my friends. It is unapologetically breakfast through and through.

It’s austere and hearty, loaded with a ton of oats, a big handful of toasted pecans, a little strawberry jam for the merest sweetness, and fresh blackberries for summery goodness.

The recipe is from the wonderfully titled new cookbook, “Life Is What You Bake It: Recipes, Stories, and Inspiration to Bake Your Way to the Top” (Clarkson Potter), of which I received a review copy.

It’s by Vallery Lomas, who knows a thing or two about the energy and sustenance it takes to forge ahead when the going’s not easy.

The Louisiana-native used to only bake for the holidays. But after taking a gap year in France after passing the bar exam, this lawyer found herself captivated by macarons. Who can blame her? So much so that when she returned to New York City to take her first job as an attorney, she somehow managed to set up a side business selling her own macarons, as well.

It wasn’t long before Lomas, who had begun the blog Foodie in New York during her last year of law school, started getting noticed. She was swayed to compete on “The Great American Baking Show,” and ended up not only triumphing, but became its first Black winner.

But the accolades that should have followed that victory were cut short when the show, taped months ahead of time, got canceled when one of its judges, Pastry Chef Johnny Iuzzini was accused of sexual harassment by employees at restaurants where he worked. As a result, the final episode, in which Lomas was declared the winner, never aired. How crushing is that?

Lomas, however, realized it was now or never, so she decided to give up her career as a lawyer to take a chance on baking full-time. She now hosts the show, “Vallery Bakes Your Questions,” on FoodNetwork.com and the Food Network Kitchen app, and contributes recipes to the New York Times.

Her cookbook is filled with 100 inviting recipes for everything from “Sweet Potato Pecan Waffles” and “Daiquiri Souffle” to “Crawfish Hand Pies” and “Granny’s Million Dollar Cake.”

This oatmeal cake couldn’t be easier. All the ingredients get stirred up in a big bowl with a wooden spoon, then tipped into a square pan to bake — just like that.

Full of oats with just enough milk and eggs to hold it all together, this cake is a little crumbly when sliced into, especially when still warm. It is fiber-rich and quite moist.

It’s also sure to give you the fortitude to tackle most anything.

Blackberry Oatmeal Cake

(Makes one 8-inch cake)

Nonstick baking spray with flour

3 cups old-fashioned rolled oats

1 tablespoon ground cinnamon

2 teaspoons baking powder

1/4 teaspoon kosher salt

6 tablespoons melted, unsalted butter, coconut oil, or vegetable oil

1 cup milk, water, or nondairy alternative, like soy or oat milk

1/4 cup packed light or dark brown sugar

1/4 cup raspberry or strawberry jam

2 large eggs

1 teaspoon vanilla extract

1 cup fresh blackberries or blueberries (see Note)

1/2 cup chopped toasted pecans (optional)

Preheat oven to 350 degrees and place a rack in the middle of the oven. Spray an 8- or 9-inch square baking pan with baking spray and set aside.

In a large bowl, combine the oats, cinnamon, baking powder, and salt.

In a medium bowl, add the melted butter, milk, brown sugar, jam, and eggs. Whisk to combine.

Pour the liquid ingredients into the dry ingredients and stir until combined. Stir in the blackberries and pecans, if using.

Pour the batter into the prepared baking pan and spread evenly. Bake until the center of the cake is set and browned along the edges, 35 to 40 minutes. Enjoy warm or at room temperature.

Storage: The can can be stored in the fridge in an airtight container for up to 4 days. To reheat, zap it in the microwave, or reheat in a 350-degree oven until warm, about 5 minutes.

Note: You can use any fruit in this dish. If using a larger fruit, such as strawberries or apples, chop them roughly before adding them to the batter. You can also skip the fruit altogether.

From “Life is What You Bake It” by Vallery Lomas

More Recipes with Oats: Minute-Oatmeal Puffs with Anise and Grapes

And: Toasted Oatmeal Pancakes

And: Espresso Chocolate Chunk Oatmeal Cookies

And: Essential Crunchy Oatmeal Cookie with Dried Mulberries

And: Triple Oatmeal Cookies

And: Brown Sugar-Oat Cherry Muffins

And: Risotto of Irish Oats