Cook the artichoke hearts, leek, garlic, shallots in butter: Melt the butter in a large, thick-bottomed pot on medium heat. Add the artichoke hearts, leek, garlic, and shallots. Cook until tender.

Add potatoes, stock, bay leaf and thyme. Bring soup to a gentle boil, then lower the heat to maintain a simmer. Cook uncovered, for 30-40 minutes, or until vegetables are fork tender.

Discard the herbs, then purée the soup using an immersion blender or a regular blender (if using a regular blender cool the soup slightly, remove the lid insert and cover loosely with a kitchen towel while blending to prevent a blender explosion!) 

Stir in salt, pepper and lemon juice, tasting and adjusting as necessary.

Place a wire rack on a large, rimmed baking sheet and line the rack with 2 layers of paper towels. Heat the canola or vegetable oil in a large saucepan until the oil registers 325° on a deep-fry thermometer. Meanwhile, using a mandolin, slice the parsnips into thin coins.

Working in batches, carefully drop handfuls of the parsnip ribbons into the hot oil and cook the ribbons over moderately high heat, stirring occasionally with a wooden spoon, until the ribbons turn a deep honey color, about 1 minute. Using a slotted spoon or skimmer, transfer the parsnips to the paper towels and sprinkle with salt. Let cool completely.

To serve, divide soup evenly amongst bowls. Top with parsnip chips and thyme leaves.