Squeeze 1/2 tsp (2 mL) juice from lemon into a medium size bowl. Whisk in sour cream, shallots, oil, water, tarragon, salt and paprika. (If making ahead, cover and refrigerate up to 2 days. Bring to room temperature before using.)
Meanwhile, fill a wide saucepan with about 2 inches (5 cm) water. Add vinegar and bring to a boil over high heat. In a large frying pan, cook bacon over medium high heat until golden tinged, about 1 to 2 minutes per side; remove pan from heat. Once water boils, reduce heat to low so water is barely simmering. Crack an egg into a small dish, then slip into water. Repeat with remaining eggs. Simmer, uncovered, until whites are set and yolks are done as you like, 2 to 4 minutes. To serve, place 1 or 2 pieces of bacon on each plate. Using a slotted spoon, remove eggs, one at a time, and dab whites with paper towel to absorb as much water as possible. Place 1 egg on a piece of bacon. Repeat with remaining eggs. Spoon about 1 1/2 tbsp (22 mL) sauce over each egg; sprinkle with chives.