Preheat oven to 350 F. Line the bottom of three  6″ straight edge cake pans with parchment paper. Spray the sides with cooking spray.

In a large bowl, whisk to combine the flour, cocoa powder, baking powder, baking soda, cinnamon and salt. Set aside.  

In a medium sized bowl, whisk the eggs, oil, sugars, buttermilk, tahini and vanilla extract until combined. 

Use a rubber spatula to gradually stir the wet ingredients into the dry ingredients. Stir until just combined, being careful not to over mix. Pour in the hot water and stir until combined.

Pour the batter evenly into the prepared pans and bake 28-32 minutes or until a toothpick comes out clean. Place pan on a wire rack and allow to cool in the pan for 30 minutes then remove from pan and cool on a wire rack. Cool completely. Once cooled, trim the tops of the cakes using a serrated knife. Wrap each layer tightly until ready to assemble. 

In the bowl of a stand mixer fitted with the paddle attachment or in a large bowl using a handheld mixer, beat the butter and tahini on medium speed until creamy and combined.

Reduce speed to low and, with the mixer running, gradually add the powdered sugar.  Add the vanilla extract, cinnamon and salt and beat on medium for about two minutes. If frosting is too thin, add more powdered sugar a tablespoon at a time. If too thin, add milk or heavy cream.

Combine the water and sugar in a medium saucepan set to medium heat. Using a light colored sauce pan is preferable so that you can better see when the sugar begins to change color. Bring the mixture to a boil and leave on a low boil over medium heat for 11-15 minutes until it turns deep reddish orange.

Remove pan from heat and whisk in the butter and cream. Once the butter has melted, stir in the salt and tahini. Pour the tahini caramel sauce over the top cake layer. Use an offset spatula, if needed, to help spread the caramel evenly. (You will have some tahini caramel leftover.)*

When ready to assemble, spoon about 1/4 of the frosting on top of the first layer. Use an offset spatula to spread the frosting. Repeat with second layer. Add the third cake layer.

Make the tahini caramel or if you've already made it, warm it in the microwave in short bursts, stirring in between until caramel is spreadable. Pour enough caramel on top layer to cover the top. Use an offset spatula to spread the caramel. Allow caramel to set for at least fifteen minutes. 

Pipe the remaining frosting on top of the caramel. Decorate with chocolate sprinkles, chocolate shavings, or sesame seeds and enjoy!