Preheat oven to 400°F or 200°C.
Drizzle oven-safe dish with a little cooking oil.
Combine milk, garlic, rosemary, thyme, salt and pepper. Whisk well to combine.
Add 1 layer of potatoes, then a mix of the other veggies. Add half of the cheese and milk mixture.
Repeat layering, end with a cheese layer.
Cook in the oven for 40-60 minutes (depending on how thick you sliced the veggies), or until potatoes and veggies are tender. Cover with thin foil for the first 30 minutes.