OP again - thank you, it's Little Inn at Washington

Just because a restaurant is good doesn’t mean it has the same style as all other similarly good restaurants.

Really depends on the particular restaurant

I went to similar restaurant recently and wore skinny black jeans and ankle boots with an elegant top and wrap, and my "occasion" jewelry. I saw a mix of dresses and pants on the women, and a mix of dress pants/blazers and jeans/polo shirts on the men.

I'd consider wearing a proper trouser with a high waist and wide leg, paired with an off the shoulder sweater or blouse. Something like this:

Pants: https://www.madewell.com/tall-harlow-wide-leg-pants-99106703045.html
Top: https://naadam.co/products/cashmere-off-the-shoulder-sweater

With some great statement earrings, and make your hair and makeup look as good as possible. I like to be comfortable when eating a really good meal, plus I get cold in restaurants often, so a skimpy dress is not my style for dinner. Plus on a dinner date, playing up my face makes sense -- my DH will be looking at my face, hair, neck, and décolletage, not my legs.

If a dress, I like the suggestion for Zara as a good budget option, though I'd opt for something a little more understated like this:

https://www.zara.com/us/en/asymmetric-neck-dress-p09015332.html?v1=221012011&v2=2113500

Leather moto jacket and ball gown

Not all Michelin 3 star restaurants are dressy and fancy so knowing the restaurant would be more informative. If you don’t want to name it, google for images (non PR/marketing ones) and look at what guests are wearing.

I like this dress with a pair of boots https://www.zara.com/us/en/printed-tulle-dress-p05039805.html?v1=203470934&gclid=EAIaIQobChMIkqbNrdHg-gIVB4nICh0BjAClEAQYASABEgKI4_D_BwE

It doesn’t matter. I usually wear a nice ish dress or classy pants and top, but I’ve seen plenty of schlubs in messy jeans before. Some restaurants don’t have dress codes and money doesn’t buy class. If there is a dress code you should absolutely abide by it.

Cocktail type dress. Or low cut silk top and black slim pants. High heels or leather boots.

Black pants, a cute top, some statement jewelry.

I don't own any dresses. I wear black jeans, loafers, and a sweater.

Which restaurant?

A dressy dress. Not too formal. Like if you were to go to a cocktail party or a romantic night out. Don’t overthink it.

Have a night coming up soon with DH for a meal at one of those super fancy 3-michelin star tasting menu type restaurants.

What do I wear (do not want to break the bank).