Ingredients & Substitutions

• Unsalted butter — Your butter needs to be at room temperature. You'll know it's ready when you can press it and leave a fingerprint, but your finger doesn't come away oily. Cold butter won't cream properly, and you'll end up with a dense brick instead of a tender pound cake.
• Sugar – I wouldn't cut back on the sugar here since it keeps the cake tender and gives it the right amount of sweetness. White sugar works best, but you can substitute cane sugar in the same amount.
• Eggs — Most of the height in this cake comes from the eggs. Make sure they're at room temperature so they mix into the cake batter easily. If you forgot to set the eggs out, place them in warm water for about 5 minutes.
• Flour — I use all-purpose flour for this recipe. I haven't tested it with cake flour, but you could substitute it for a 1:1 ratio. Use the same amount in grams. If you give it a go, I would love to hear how it turns out in the comments below!
• Baking powder—Helps this delicious pound cake rise.
• Sourdough Discard—When I'm making sweet recipes like this sourdough discard pound cake, I like to use fresh discard, no older than 2 days, for the best flavor. Older discard gives this pound cake a tangier flavor. If a little tangier is your idea of the perfect pound cake, definitely use older discard. You can also use an active sourdough starter. If you go with an active starter, be sure to use the same amount by weight, not volume.
• Sour Cream—Gives this pound cake a moist crumb and adds a little tang that balances the sweetness. You can swap it for Greek yogurt if that's what you have on hand.
• Salt—I add a pinch of sea salt for the minerals and extra flavor. 
• Extracts—I use a mix of vanilla and almond extract. The almond extract adds a subtle, nutty depth that plays really nicely with the vanilla, but you can leave it out if you'd rather keep things simple.

Tips

• For that classic cracked top, place a small slice of cold butter in the center of the batter right before it goes into the oven.
• Make sure all your ingredients are at room temperature before you start. Cold ones make blending the batter a little tougher, and you'll end up with a curdled-looking batter that doesn't come together the way it should. My Sourdough Apple Cake has the same creaming step, and cold butter causes the exact same problem there.
• Don't overmix once the eggs go in, or you'll have gummy streaks running through the cake. My Sourdough Coffee Cake has the same sour cream and discard base, and the same overmixing rule also applies to the recipe