Preheat oven to 350°. Spray 3 (9-inch) round cake pans with baking spray with flour. Line bottom of pans with parchment paper; spray pans again.
In a large bowl, beat butter and sugar with a mixer at medium speed until fluffy, 3 to 4 minutes, stopping to scrape sides of bowl. Add eggs, one at a time, beating well after each addition. Beat in vanilla.
With mixer on low speed, gradually add flour to butter mixture alternately with buttermilk, beginning and ending with flour, beating just until combined after each addition. Divide batter among prepared pans.
Bake until a wooden pick inserted in center comes out clean, 25 to 30 minutes. Let cool in pans for 10 minutes. Remove from pans, and let cool completely on wire racks. Spread Caramel Frosting between layers and on top and sides of cake. Drizzle with reserved ⅓ cup caramel from Caramel Frosting. Garnish with pecans, if desired. Store in an airtight container for up to 3 days.
Caramel Frosting
In a large heavy-bottomed saucepan, whisk together granulated sugar, ¼ cup water, and corn syrup just until sugar is moistened. Cook over medium-high heat, without stirring, until mixture is golden brown. (While caramel cooks, brush any sugar crystals on sides of pan with a pastry brush dipped in water.)
Remove from heat, and carefully stir in ½ cup butter until melted. Slowly stir in cream until smooth. Let mixture cool until just warm, about 1 hour, stirring occasionally. Reserve ⅓ cup caramel in a small bowl.
In a large bowl, beat remaining caramel and remaining 1 cup butter with a mixer at medium speed until smooth. Gradually add confectioners’ sugar, beating just until smooth. Cover with plastic wrap, and let stand until frosting has reached a spreadable consistency, about 10 minutes.
Recipe by Taste of the South at https://tasteofthesouthmagazine.com/caramel-layer-cake/