Curried Zucchini Soup

I'm surprised I haven't posted this yet, I make it so often! I don't have a picture anywhere, but you can take my word that it is DELICIOUS!!!!! =D

Curried Zucchini Soup
1 red onion, diced
2 garlic cloves, minced
2 carrots, shredded
1 tbsp butter
2 medium zucchinis, diced
2 apples, peeled and diced
4 cups soup broth (I usually use veggie)
1.5 tsp curry (or more)

In large pot, melt butter over low heat. Saute onion, garlic, and carrot slowly until onion becomes translucent. Add zucchini, apple, broth, and curry. Boil for 2 minutes; reduce heat to low, cover, and simmer for 20 minutes.
Carefully puree hot soup in blender in small batches. Add salt and pepper to taste (optional).