Vegetable Curry (with chicken, if you want)

Ingredients

• 5 cloves garlic
• 1 (8cm) chunk peeled, fresh ginger
• 1 tbsp water, plus more as needed
• 60ml vegetable oil
• 1/2 tsp coriander seeds
• 1/4 tsp cumin seeds
• 6 green cardamom pods
• 4 whole allspice
• 3 whole cloves
• 1 (8cm) long cinnamon stick, broken in half
• 1 bay leaf, preferably fresh
• 1 medium yellow onion, sliced
• 2 tsp Madras-style curry powder
• 1/2 jalapeno, or more to taste
• 120g whole, peeled, tinned tomatoes (with puree), roughly chopped
• 800g mixed 2.5cm-cut vegetables, such as cauliflower, potatoes, French beans, or eggplant
• Salt and freshly ground black pepper
• 1 (400g) tin unsweetened coconut milk
• About 200g (2.5cm cubed) cooked chicken, preferably thigh or leg (optional)
• Coriander leaves, for garnish
• Serving suggestion: Basmati rice and chutney