To concoct something means to create or make something new by combining different things together. It can also mean to mix or blend substances.
When we say someone has concocted a plan, it usually means they've come up with an idea by putting various pieces together. This could be a business idea that involves combining several strategies and resources, or a recipe that mixes flavors from different cuisines. A chef might concoct a new dish by blending unusual ingredients, like sweet potatoes with spicy peppers. In these cases, the person is making something new out of existing parts, often in a creative way.
To prepare something by mixing various ingredients, especially to prepare food for cooking.
Example: to concoct a new dish
