1. Preheat oven to 350°. Whisk together dry ingredients (flour, sugar, salt, baking soda, guar gum, and cinnamon) in a large bowl.2. Over medium heat, melt butter. Whisk in cocoa powder. Add boiling water, and boil mixture for 30 seconds. Remove from heat and pour over flour mixture. Whisk to combine. 3. In a separate bowl, combine yogurt, milk, eggs, and vanilla. Whisk to combine then fold into chocolate batter.4. Pour batter into 18x13 baking sheet and bake for 20 minutes. 5. While the cake bakes, let’s make the frosting! Melt the butter in a saucepan. Add cocoa powder and remove from heat. Add milk, vanilla and powdered sugar. Whisk together until no clumps of sugar remain.6. Once the cake has cooled for 15 minutes, pour the frosting over the cake (and sprinkle pecans over top, if you wish). 7. Cut into squares and ENJOY!