The best option to bring to a BBQ is salad:
Filling carbohydrate salads - such as potato or pasta salad;
Green salads - tomato-cucumber-avocado salad, or broccoli salad;
Fruit salads - watermelon and feta cheese salad, sweet, creamy fruit salad (it's more of a dessert than a salad);
Meat and fish salads - tuna salad, chicken salad, salmon salad;
Bean salads - lentil salad, baked beans, and bacon salad
You can also ask the host what they need/want.
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