Preheat your oven to 350°F (175°C). Line a 8.5x4.5-inch loaf pan with parchment, leaving overhang for easy lifting.
In a large bowl, whisk together 2 cups sunflower seed flour, 2 tablespoons psyllium husk powder, 2 teaspoons baking powder, and 1/2 teaspoon sea salt.
In a separate bowl, whisk 4 large eggs, 1 cup unsweetened almond milk, 3 tablespoons olive oil, and 1 tablespoon apple cider vinegar until smooth.
Pour the wet ingredients into the dry.
Stir until evenly combined. The batter will thicken quickly as the psyllium hydrates. If it looks dry, add 1–2 tablespoons more almond milk.
Fold in any optional add-ins like 2 tablespoons seeds or 1 teaspoon dried herbs.
Spoon the batter into the prepared pan.
Smooth the top with a spatula. For a rustic look, score a shallow line down the middle.
Bake for 45–55 minutes, until the top is set and a toothpick comes out clean. The loaf should spring back lightly when pressed.
Cool in the pan for 10 minutes, then lift out using the parchment and transfer to a wire rack.
Let cool completely before slicing for best texture.
Slice with a sharp serrated knife. Enjoy toasted with butter, avocado, or your favorite low-carb toppings.