Preheat oven to 350 F. Grease and flour three 6-inch (or two 8-inch) cake rounds and line with parchment paper.1 Set aside.
In a medium bowl, whisk flour, baking powder, and salt together. Set aside.
In a measuring cup, stir together maple syrup and milk. Set aside.
In the bowl of a stand mixer fitted with a paddle attachment, mix butter and sugar on medium-high speed until light and fluffy, about 3 minutes). Turn speed to low and add eggs one at a time, beating well after each addition.2 Add vanilla and mix until combined. Scrape down the sides of the bowl as necessary.
Alternate adding flour mixture and maple mixture, beginning and ending with flour (3 parts flour and 2 parts maple). Mix well after each addition.
Bake for 30-35 minutes or until a toothpick inserted in the center comes out with little to no crumbs.
Let cakes cool in the pan for 10 minutes, then turn on to a wire rack to cool completely. Prepare the frosting.
In the bowl of a stand mixer with a paddle attachment, beat the butter and cream cheese together on medium-high speed until light and fluffy, about 2 minutes. Add the maple extract, vanilla extract and salt, and beat until combined, about 1 minute more.
With the mixer on low, slowly add in the confectioners' sugar and beat until combined, about 1 minute. Scrape down the sides and bottom of the bowl if necessary.
Place the first cake on a plate, then top with a scoop of frosting and spread evenly. Top with the second layer and frost again (repeat if doing three layers). Finish by frosting the outside of the cake with the remaining frosting. Garnish with pecans (or spiced pecans).