In short
✓ The bain marie is the safest method to melt chocolate without burning it: a bowl placed on a pan of hot water, that's all.
✓ The water in the pan should never boil — keep it between 50°C and 60°C to protect the chocolate from excessive heat.
✓ The bowl must not touch the water and must be perfectly dry: a single drop of water is enough to make the chocolate set.
✓ Dark, milk and white chocolate do not have the same melting temperatures — respect the thresholds of each type for a smooth and shiny result.
✓ A chocolate that burns or separates almost always has a solution: adding warm cream or gently reheating over low heat.