Cooking up a storm. 10 Gamerscore.

After you get your pistol and the SMG mod, you will need to walk further through the base and you will be prompted to build a molotov cocktail from components on a nearby table, you'll see the items on the table. Follow the screen prompts and hold the cn_A button until the circle around it is filled and lite up and as the molotov item is added to inventory, you will unlock this Achievement.