Ribarska Hiza — "fisherman's hut" — is the archetype of the Bulgarian Black Sea restaurant: a relaxed, unfussy place serving fresh fish from the local catch alongside Bulgarian salads, grilled vegetables, and cold beer. The decor runs to fishing nets and wooden beams. The fish is the point. Black Sea bass (lavar), turbot (kalkan), and sprat (tsatsa) are the varieties to look for, all typically grilled simply with oil and lemon.
Restaurants of this type cluster in and around Varna's old centre and down by the port. Prices are very reasonable by Western European standards. The key is to ask what came in that day and order accordingly — the fish that's been sitting longest won't be worth eating regardless of how it's prepared. Go for lunch if possible, when the catch is freshest.