Heat oil in a large deep frying pan or flameproof wide, shallow casserole dish over a medium-high heat. Add onion and garlic. Cook, stirring for 2 minutes or until light golden. Add mushrooms and thyme. Cook, stirring a further 2-3 minutes, or until mushrooms are just tender. Stir in rice.
Dissolve stock cube in 3 ½ cups hot water in a large jug. Pour half the stock into pan. Bring to boil. Reduce heat to low. Simmer gently, uncovered, for about 10 minutes, stirring often, until most of the stock has been absorbed.
Stir in remaining stock. Simmer, stirring often for 5 minutes. Stir in lentils. Simmer a further 3 minutes, or until most of the stock has been absorbed and rice is just tender (al dente). Stir in spinach until just wilted.
Remove from heat. Stir in pinenuts and 1/3 cup parmesan.
Divide into 4 serving bowls. Season with freshly ground pepper. Serve sprinkled with remaining parmesan.

Reduce the prep time by replacing button and Swiss brown mushrooms with a 400g packet pre-sliced fresh mushrooms available from the fruit and vegetable department in supermarkets.
Substitute 1 teaspoon dried thyme leaves for fresh thyme, if preferred.
To toast pinenuts, stir in a small, dry frying pan over a low-medium heat until light golden.
Arborio is a type of short grain rice that gives risotto its creamy texture.
Any leftover risotto can be refrigerated and served as a tasty lunch the following day. Store, covered, in the fridge. Reheat in microwave oven just before serving.
Replace pine nuts with any toasted nuts or seeds.
Try pepitas or chopped natural almonds.