• Put the potatoes, garlic and milk in a large pot over medium-high heat.
• Bring to boil.
• Add the cauliflower.
• Cook 10 to 15 minutes or until the potatoes and cauliflower are tender.
• Drain vegetables and reserve 1/2 cup of the cooking liquid.
• Puree the vegetables in a food processor with the cooking liquid and heavy cream.
• Season with salt and pepper, and add the lemon juice.
• Reheat before serving.

Stewed mushrooms:

• Pour oil in a large skillet over high heat.
• Sauté shallots and garlic for 30 seconds.
• Add mushrooms and thyme, and sauté until the mushrooms have rendered their juice (about 4 minutes).
• Season with salt and pepper.
• Add wine and bring to a boil.
• Let reduce to thicken the sauce slightly (about 5 minutes).
• Reduce heat to low and add the butter.
• The sauce will thicken a little more.
• Simmer until the mushrooms are coated with the sauce (2 minutes).
• Adjust seasoning if necessary and add the parsley.
• Pour a ladle of mashed cauliflower into bowls.
• Top with mushrooms and drizzle with a little sauce.