Grate 12 tablespoons butter on a large hole grater.
In a mixing bowl, combine 2 cups (250g) all-purpose flour, ½ cup (60g) rye flour, 1 tablespoon baking powder, 4 teaspoons dried chives, 1½ teaspoons dried dill, 1 teaspoon salt and 1 teaspoon sugar.
Add shredded butter to flour mixture and lightly mix with fingers until combined and butter pieces are completely coated in flour.
Add 1 tablespoon Better than Bouillon to a liquid measuring cup. Add a splash of buttermilk and whisk until combines and smooth. Add buttermilk to reach 1 cup mark.
Form a well in center of flour butter-mixture; pour buttermilk mixture into well. Using a spoon, mix dough gently until a dough comes together.
Transfer dough to a work surface and lightly press dough into a rough 8✕5-inch rectangle (about 1-inch thick)
Fold rectangle into thirds (like a letter) and press down into a 1-inch thick rectangle. Repeat folding and pressing twice more.
Shape rectangle into a rough 8✕5-inch rectangle (about 1¼-inches thick). Transfer to a parchment lined baking sheet and chill 30 minutes.
Meanwhile, heat oven to 450ºF (232ºC) with rack set in middle position.
Cut biscuit dough in half lengthwise then cut each half into 4 squares.
Arrange biscuits about 2 inches apart on parchment lined-baking sheet.
In a small bowl, melt remaining 4 tablespoons butter in microwave in 20 second increments on 80% power. Add 2 teaspoon Better than Bouillon and 2 teaspoon dried chives. Brush biscuits with seasoned butter then sprinkle flaky sea salt over top.
Bake until tops are golden brown and crisp, about 20 minutes. Remove from oven and let cool on sheet 5 minutes before transferring to a wire rack.
Brush biscuit tops with additional seasoned melted butter mixture and serve.