Greek tomato, orzo, and feta soup

Ingredients

• 7 oz orzo
• 14 oz canned diced tomatoes
• 5 oz feta cheese
• 2 cloves garlic
• 1 onion
• 4 tbsp olive oil
• 4 cups vegetable broth
• 1/2 tsp chili flakes
• 1 tsp ground allspice
• 1 1/2 tsp dried oregano
• 3 tbsp tomato paste
• 1 lemon
• 1 tsp sugar
• salt
• pepper