Preheat the oven to 180ºC. Cut the pumpkin into wedges and de-seed it. Spread the pumpkin out on to one or two lined baking trays. Drizzle the juice of 1/2 lemon and 1/4 cup of olive oil over the pumpkin and roast for 30 minutes then set aside to cool.
To make the dressing: combine remaining lemon, olive oil, mustard and stir.
To serve, lay the spinach out on to the serving plate and place pumpkin wedges on top. Top with pomegranate seeds, pepita seeds, capers and lentils. Pour over the dressing.
