Soak lentils in 6 cups cool water for 4 to 8 hours to make them more digestible and reduce anti-nutrient content.
Drain well after soaking.
Add 5 cups fresh water and lentils to a pot and bring to a boil. Reduce heat to simmer and cook 20 to 30 minutes, until it looks like a slurry and almost no liquid remains.
If beans are still watery, drain them through a fine mesh strainer, otherwise just let cool.
Allow lentils to cool for 20-30 minutes.
Add beans, 1 1/2 teaspoons (8 ml) salt and mince garlic and add to the bowl of a food processor. Squeeze lemon juice in and add umeshu. Process on low to incorporate ingredients for 10 to 15 seconds.
Remove dill fronds from stems and mince. Add tahini, lemon juice and dill to bowl. Process until it starts to become smooth.
Drizzle olive oil into food processor while spinning for another 20 seconds.
Transfer to a serving or storage bowl.
Chop pickles into 1/4" (1 cm) size cubes and stir into serving bowl. Garnish with thinly sliced pickles if desired.
Due to the high protein content, hummus is relatively perishable (compared to most other recipes up in here!) Will keep for refrigerator for 3 days.