25th Anniversary in Florence

Hi. I’m jealous. And I really don’t have a specific answer for you. But I believe your question might better be framed by describing what type of experience you want to have for the meal. Formal 5 star or intimate, authentic, local.
I’m posting because we stayed in two different hotels in Florence, one in downtown and the other in the alto-Arno the Hotel Silla (Sella?) recommended by Rick. I adored the second hotel and surroundings and remember eating in three places in the same neighborhood in one evening. Wine and bruschetta up the hill slightly behind the hotel a little vino bar, a meal closer to the hotel on a little square and a gelato across the square. We did use RS recommendations for meals that were excellent. Florence has more meat (wild boar) and beans.So the type of food you want is helpful too. Avoid tourist traps. If you don’t get suggestions from anyone pick your favorite description from Ricks book and make reservations ahead. Your hotel concierges should be able to assist as well. Best wishes.

Budget: Up to $300
I like to have memorable food experiences. The ambiance doesn’t necessarily need to be “romantic”, the food has to be awesome. Local specialties preferred.

One restaurant that I think meets all your criteria is Ristorante Cibreo (not to be confused with the same owner's Trattoria, Cafe or new Tuscan Oriental restaurant). While it is listed in some guidebooks, it's still suitable for a 25th anniversary splurge without breaking the bank. Some others that came to mind would probably be over $300 (about 265 euro) with a nice bottle of wine, so no point in mentioning them by name.

Flavio al Velavevodetto inside the Testaccio hill. Reservations a must ---- look at their online booking to make sure you are reserving far enough in advance. Tourists eat early, Romans start arriving at about 8:45pm.

Testaccio is in Rome, so that restaurant won't work.

I could go there when I'm in Rome, though.

Check this lovely restaurant, not only for the view but the gastronomic experience. $$$

https://www.hotelbaglioni.it/media/grand-hotel-baglioni/B-ROOF%20menu.pdf

That menu is appealing.