This very small top gourmet restaurant needs reservation (maximum: 8 people), as it has 49 seats only. Try a test menu (5 to 7 courses, for example Hungarian Evolution, or Onyx Prestige). It is also known for the Onyx Lunch. Respect dress code (lunch business casual, dinner: semi formal). Chef Szabina Szulló and sauce chef Tamás Széll have twice won the most prestigious National Hungarian cooking competition and are eager to present quality products and innovative dishes.