Cook the gnocchi in a large pan of boiling water, according to package instructions (usually 2 minutes), then drain well.
Heat the butter in a frying pan, add the cooked gnocchi and fry for a few minutes, turning often, until golden.
Meanwhile, heat the oil in a large pan or frying pan over a medium/low heat, then add the mushrooms, garlic and thyme and cook until soft and the mushrooms have released their juices. Add the cream and stir to combine.
Divide the gnocchi between four plates and serve topped with the mushroom sauce.