Start by peeling and cutting the pumpkin into evenly sized wedges. Keeping the pieces uniform helps them cook at the same rate. Toss them with olive oil, salt, and pepper to coat well.
Spread the pumpkin pieces on a lined baking tray in a single layer. Roast in a preheated oven at 200°C (390°F) until they turn golden and tender. Flip halfway through for even browning.
In a bowl, combine yogurt, grated garlic, and lemon juice. Mix until smooth and creamy. Taste and adjust salt if needed for a balanced flavor.
Heat a small pan over medium heat and toast the pine nuts until lightly golden. Keep stirring as they can burn quickly. Remove from heat once fragrant.
Spread the yogurt sauce on a serving plate as the base. Place the roasted pumpkin on top gently. This layering helps every bite get some sauce.
Sprinkle toasted pine nuts over the pumpkin. Drizzle a little olive oil and add chopped herbs if using. Serve warm or at room temperature.