In a bowl, combine 3 ½ cups of flour, 2 tablespoons of baking powder, 2 teaspoons of baking soda, and 1 teaspoon of salt.
Grate 2 1/12 sticks of butter into the dry ingredients.
Mix the butter into the dry ingredients with your hand, until the butter is incorporated and the pieces no bigger than the size of a pea.
In a separate bowl, combine 2 eggs, 1 cup of cold buttermilk, and 1 cup of sourdough starter. Whisk until thoroughly incorporated.
Combine the wet and dry ingredients. Mix thoroughly until a dough has formed.
Place the dough in the fridge for at least 30 minutes but up to 12 hours. This can allow the sourdough to ferment.
Preheat the oven to 400 degrees and line a loaf pan with parchment paper on all four sides or grease the entire loaf pan.
Scrape the dough onto a floured surface. Pat it into a rectangular 9x13 shape, about a half-inch thick.
In a bowl, combine the 4 tablespoons of melted butter, ½ tablespoon of onion powder, ½ tablespoon of garlic powder, 1 tbsp of chives, and ½ tbsp of salt.
Spread the butter mixture over the biscuit bread dough.
Using a knife or pizza cutter, cut the biscuit dough into approximately 15-20 squares.
Layer the biscuit dough squares into the loaf pan. Play around with how you want the biscuit squares to fit in because you don’t want them to be stacked one in front of the other. Ideally, layer them staggered with one on the left side of the pan and then one on the right. Repeat this until there is no biscuit dough left. You will need to push the biscuit dough into the loaf pan for it all to fit.
Place the loaf pan on a baking sheet before you put it in the oven. You can line the baking sheet with tin foil for an even easier clean up too!
Place your Garlic and Chive Biscuit Bread into the oven at 400 degrees for about 45 minutes. After 20 minutes, cover the biscuit bread with tin foil to prevent over-browning. The bread is done when the internal temperature measures 195 degrees.
Let the biscuit bread cool in the pan for about 10 minutes and then remove it using the parchment paper. You may need to loosen the edges with a butter knife if you did not use parchment paper.
Top with the remaining chopped chives and serve hot!