Make the lentils: In a large saucepan, combine the lentils, garlic, thyme, lemon zest, and one quart of water. Bring to a boil, then reduce the heat to low and simmer for 35 to 40 minutes, until the lentils are tender. If the lentils are looking dry, add a little more water. If your lentils are cooked through, but there is still water in the pan, strain them.
Remove the lentils from the heat and discard the thyme and lemon zest. Remove the garlic cloves and squeeze out of the peel into a small bowl. Mash with a fork and mix back into the lentils. Add the olive oil and vinegar and season with salt and pepper.
Make the dressing: In a small bowl, whisk all the ingredients together until smooth. Season with salt and pepper as desired.
Place salmon on top of two lettuce leaves, to make one cup. Drizzle the kefir dressing over and garnish with dill and pomegranate seeds. Sprinkle with flaky sea salt as desired.