Preheat oven to 350°F.
Mix crackers and 4 tablespoons butter. Press into bottom and sides of an 8-inch pie dish. Chill crust.
Melt remaining 2 tablespoons butter in skillet. Add onions and garlic. Cook over medium heat until soft (about 12 minutes).
Spread onion mixture in crust.
In a bowl, whisk eggs, milk, salt, and chives. Pour over onions. Top with cheddar cheese and a sprinkle of paprika.
Bake for 35 minutes or until set. Let cool slightly, garnish with parsley, and serve warm or at room temperature.