Prep everything first: halve and pit the avocado, thinly slice the radishes, measure the sunflower seeds, and separate eggs into individual small ramekins or cups. Having everything prepped lets you time the toast, seeds and eggs so every element is served at its ideal temperature and texture.

Toast the sourdough until golden and crunchy (use a toaster or oven at 200°C/400°F for about 5–7 minutes). A well-toasted slice creates a sturdy base — it prevents sogginess from the avocado and provides a satisfying crunch to contrast the soft egg and creamy avocado.

Toast the sunflower seeds in a dry skillet over medium heat for 2–3 minutes, shaking the pan frequently until they smell nutty and are lightly golden. Toasting releases the seeds’ oils and adds a warm, toasty aroma and extra crunch; watch carefully so they don’t burn.

Make the smashed avocado: in a bowl, scoop the avocado flesh and add the lemon juice (1 tsp per serving), a pinch of salt and a grind of black pepper. Gently smash with a fork, leaving some small chunks for texture rather than making a smooth purée. The lemon brightens flavor and prevents browning; leaving texture adds mouthfeel against the toast.

Bring a wide saucepan of water to a gentle simmer (not a rolling boil) and add the optional 1 tbsp white vinegar — the vinegar helps the egg whites coagulate more quickly so the poached egg keeps a neat shape. Aim for a water temperature of about 80–90°C (180–195°F).

Create a gentle whirlpool by stirring the water, then slip one egg from its ramekin into the center. The swirling water helps wrap the white around the yolk for a tidy poach. Poach for 3 minutes for a soft runny yolk, or 3¼–3½ minutes if you prefer the white firmer. Use low simmering water to prevent the egg from breaking apart.

Remove the egg with a slotted spoon and briefly drain on paper towel. If you’re cooking two eggs, poach them one at a time (or space them far apart in the pan) so the water temperature stays consistent — overcrowding cools the water and results in ragged whites.

Assemble: spread half the smashed avocado over each toasted sourdough slice. Spreading while toast is still warm helps the avocado adhere and warms the topping slightly for a melded flavor experience.

Layer the thin radish slices over the avocado for a crisp, peppery counterpoint. Scatter the warm toasted sunflower seeds on top — the contrast between warm seeds and cool radish/avocado elevates texture and flavor.

Gently place a soft-poached egg on each toast. Finish with a few microgreens or arugula, a generous pinch of flaky sea salt, a crack of black pepper and a light dusting of chili flakes for heat. The final seasoning in layers ensures bright, balanced flavors in every bite.

Serve immediately so the yolk remains runny and the toast stays crisp. Encourage diners to cut through the egg so the yolk streaks over the avocado and toast for the classic, luscious finish.