Before you start, bring a large pot of salted water to the boil.
Prep onion. Heat oil in a large, deep fry-pan on high heat. Cook onion for about 3 minutes, until starting to brown. Add fennel seed spices, almonds and a pinch of salt and cook for a further 2-3 minutes, stirring, until almonds are toasted. Add balsamic glaze and cook for 30 seconds, until onion is sticky and golden. Set onion aside and wipe pan clean.
Cut any larger mushrooms in half and leave smaller ones whole. Prep leek, thyme and lemon and set aside.
Cook gnocchi in pot of boiling water for 2-3 minutes, until starting to float. Drain and toss with olive oil to prevent sticking.
Heat oil in reserved pan on high heat. Cook mushrooms and leek for 6-7 minutes, until softened and browned. Add thyme and a pinch of salt and cook for 1 minute, until fragrant.
Reduce heat to medium, add stock, porcini powder mix (if using), lemon juice, peas and spinach to pan and bring to a simmer. Once simmering, stir through cooked gnocchi and a pinch of salt and simmer for a further 2 minutes, until peas are tender. Remove from heat, stir through garlic sour cream and season to taste with salt and pepper.
Serve gnocchi topped with onion and any remaining thyme leaves.