Set the oven to 180°C / 350°F with the fan.
Cut the mushrooms and place them on a baking pan.
Drizzle the olive oil, salt, and pepper on the cut mushrooms.
Roast for 10-15 minutes until mushrooms start to release liquids and turn darker.
Set the mushrooms aside to cool.
Place the cauliflower florets in a pot, cover with boiling water and cook for 10-15 minutes to the level of tenderness you like.
Strain the cauliflower from the water and set it aside to cool.
Place the black lentils in a pot and add cold water to cover.
Cook on high for 30 minutes until lentils turn soft and fully cooked.
Strain the lentils and set them aside to cool.
In a small bowl, mix all the dressing ingredients well.
In a big bowl, place the lettuce and add the cauliflower, mushrooms, and lentils.
Drizzle the dressing over the salad.
Mix well.
Serve and enjoy!