Easy Parsnip Soup

• 1 tbsp extra virgin olive oil
• 1 brown onion, chopped
• 1 tsp garlic powder (for fresh garlic, grated)
• 1 tbsp ginger, grated
• 1 tbsp curry powder
• 1 kg parsnips, chopped
• 1.5 l vegetable stock
• 500 ml milk