Preheat your oven to 350 degrees F. Grab a 9x13-inch baking pan and grease it well to prevent sticking.
In a medium bowl, combine the boiling water, raisins, and oats. Stir them together and let the mixture sit for 20 minutes. This step allows the oats to soften and absorb the flavors.
While the oats are soaking, prepare the dry ingredients. In a small bowl, whisk together the all-purpose flour, baking soda, ground cinnamon, ground nutmeg, and salt. Set this mixture aside.
In a large mixing bowl, use an electric mixer to beat the unsalted butter and both granulated and light brown sugar together on high speed until the mixture is light and fluffy, about 5 minutes. This step is essential for incorporating air into the batter.
Reduce the mixer speed to medium, and add the eggs and vanilla extract to the butter and sugar mixture. Beat until everything is well combined.
Now, it’s time to add the oat mixture to the mixing bowl. Reduce the mixer speed to low and gently incorporate the soaked oats and raisins.
Gradually add the dry flour mixture to the batter, beating until just combined. You don’t want to overmix, as this could make the cake dense. Give the mixture a final stir using a rubber spatula to ensure everything is well combined.
Carefully transfer the batter to the prepared baking pan, spreading it evenly.
Bake in the preheated oven for about 40 to 45 minutes, or until the cake is golden brown and a toothpick inserted into the center comes out clean. The aroma will fill your kitchen, making everyone eager to taste!
Once baked, remove the cake from the oven and place it on a wire rack to cool completely before frosting.
To make the cream cheese frosting, in a clean mixing bowl, beat together the cold cream cheese and unsalted butter on medium-high speed until smooth, which should take about 3 minutes. It’s important to start with cold cream cheese for the best texture.
Reduce the mixer speed to medium-low and gradually add in the powdered sugar, mixing until fully incorporated.
Finally, add the remaining vanilla extract and a pinch of salt. Increase the mixer speed back to medium-high and beat until you have a light and fluffy frosting, about 2 minutes.
Spread the cream cheese frosting evenly over the cooled cake. Now, slice and serve your lovely Oatmeal Raisin Snack Cake to friends and family. Enjoy!
