To poach the egg, fill a poacher pan with water (up to the rivet). Add a dash of white vinegar and bring water to a simmer over medium heat.
Add egg basket to the poacher pan with basket handle facing the rim of the pan.
Crack the egg into a separate bowl, then gently pour it into the egg basket.
Cook the egg for about 3 1/2 minutes.
Lift up the basket to remove it from the water using the stay-cool handle. Tip basket to drain out any excess water back into the pan, then gently slide the egg out onto a paper towel to remove any excess moisture.
Toast the bagel or bread and spread with cream cheese.
Top with salmon and gently spoon the poached egg on top.
Garnish with capers, if desired.