Irish Cheddar Spring Onion Biscuits

Ingredients (6)

• + 2 cups self-rising flour, plus more for kneading add to pantry
• ✓ ¼ teaspoon baking soda
• + 7 tablespoons very cold butter, cut into pieces add to pantry
• + ¾ cup buttermilk, plus additional for brushing add to pantry
• + ½ cup shredded Irish Cheddar cheese, divided, plus more for topping add to pantry
• + ¼ cup sliced green onions, divided add to pantry