In a large bowl whisk together 1 cup warm water (115°F), 1 cup low-fat buttermilk, 100 grams sourdough discard (or active starter), 1 large room-temperature egg, 2 Tbsp extra-light olive oil (or vegetable oil), 3 Tbsp granulated sugar, 1 ½ tsp instant yeast, and 1 ¼ tsp fine sea salt until combined.
Add 2 2/3 cups all-purpose flour (330 grams) to the bowl 1 cup at a time, whisking to incorporate each addition before adding more. After all the flour is added, whisk until the batter is smooth and has a cake-batter consistency.
Cover the bowl with plastic wrap and let the batter rise: at room temperature for 1½ to 2 hours, or in a warm place (about 100°F) for 1 hour. The batter is ready when it has roughly doubled in size and appears very bubbly and airy.
Preheat a large nonstick skillet over medium heat. Add a generous drizzle of oil to lightly coat the bottom of the skillet and let the oil heat until it shimmers.
Spoon portions of batter into the hot skillet (a release-style scoop works well). Cook until the edges are golden and bubbles form on the surface, about 1 to 1½ minutes, then flip and cook the other side until golden, about 1 to 1½ minutes more. Add more oil to the pan as needed after flipping. If pancakes are browning too quickly, reduce the heat.
Transfer cooked pancakes to a wire rack or serving platter to keep them from steaming on the hot pan. Serve warm.