Start by poaching the eggs, one egg per toast.
Bring a saucepan of water to a boil and add 2 tablespoons of vinegar.
Crack an egg into a small cup.
When the water reaches a gentle boil, stir it in the center with a spatula to create a whirlpool.
Gently slide the egg from the cup into the whirlpool, letting the cup touch the water.
Fold the edges of the egg over to enclose the yolk and cook for 3 to 4 minutes.
Check the doneness by lifting the egg with a slotted spoon and gently pressing the yolk with your finger. Adjust the cooking time if you prefer the yolk more or less runny. For a semi-runny poached egg, the yolk should feel slightly soft but not too wobbly under light pressure.
Remove the egg from the water and place it in a bowl of very cold water, ideally with ice cubes, to stop the cooking.
Then place the eggs on a paper towel to drain.
Spread the toasts with mashed avocado, and place a poached egg in the center of each.
Cut the egg in half to let the yolk run out. Arrange halved cherry tomatoes and a few capers around it.
Sprinkle with chia or poppy seeds and a little chopped chives.