If you suspect that your meat or poultry is a little less tender than it should be, then braise it. Braising involves cooking the meat slowly and gently in a liquid, generally broth, fruit juice, or vegetable juice. Avoid using milk-based products, because they will curdle in the heat.
Be realistic, and expect to have to pay a significant amount for the privilege of eating in a gourmet restaurant. Gourmet food often uses expensive and rare ingredients and requires a great deal of preparation, so it's bound to be costly. A good gourmet meal, though, is worth every cent.