For Slovenian cooking: book the style you want
Druga Violina, on Stari trg, is the straightforward choice for familiar Slovenian dishes in the old town; it is popular with groups, so book dinner in busy months. Gostilna As near Čopova ulica suits a longer, more polished meal and has a broad Slovenian-Mediterranean menu. Expect a sit-down meal in the middle price range rather than a cheap snack at either. Order štruklji or Idrija žlikrofi when they are on the menu, but do not assume every restaurant serves every regional dish every day.
For a small-plates dinner: stay near the river
TaBar is a useful choice for Slovenian wine and shareable plates, especially if you want dinner that is different from a heavy gostilna meal. Reserve ahead for an evening table; its compact room fills quickly. Around the river and in the old town, prices climb with the setting, so compare menus before sitting down on the promenade. A coffee or drink on the water is worthwhile; a full dinner there is best chosen for the menu, not simply the view.
For quick, inexpensive food: go where people actually eat between errands
Sarajevo ’84 on Nazorjeva is a long-running option for Balkan grilled meat and a fast, casual meal. The Central Market area is better for daytime grazing than a late dinner: look for seasonal produce, bakery items, cheese and cured meat, and check which stalls are operating on the day. Odprta Kuhna, the open-air food market on Pogačarjev trg, normally runs on selected Fridays in the warmer part of the year; check its official schedule before arranging your visit around it.
Make the timing work
Ljubljana restaurants often take a pause between lunch and dinner, and kitchens can close earlier than visitors expect on Sunday or Monday. Booking is sensible for Friday and Saturday evenings, even outside high summer. A simple bakery lunch or grill can keep spending low; wine bars, riverfront terraces and tasting menus push the bill up quickly. The city centre is walkable, so choose by meal rather than by neighbourhood: use the market at lunch, the old town for a booked dinner, and the station side for a quick arrival-night meal. Pair meals with the Ljubljana sights route or choose an area from where to stay.