While I'm thinking about it, Steak Tartare...
Mignon in Plano. Tartare is always available for the asking. (We ask every time. Ask when you arrive and sit down.) Recipe can vary a little, but always good. Don't know the price. You can be jeans and golf shirt casual in the bar; add a sweater for the dining room. You'll run in to suits and cocktail dresses, but also jeans and nice button downs. We always get in when we want. We kind of reserve a spot by using open table 10 minutes before we leave to drive over to the restaurant.
Mignon - Prime Steaks, Seafood and Cocktails
4005 Preston Rd., Plano, TX 75093
Toulouse Cafe on Knox is very approachable.
Local. Haven't been in a while and needs props.
St Martin's version is really nice for 12 bucks.
The Grape had it at one time but the menu changes often. Ask for it, chef is accomodating.
Mercury had it on the menu but its been a LONG time since I have been here, can't imagine it not being on the menu now.
Bolla serves tartare, and it is REALLY nice
Steel has beef tataki. Eh, had to mention.
Dallas Chop House, Nana Bar, Sullivan's, Bob's, Del Frisco, Al's & Nick and Sam's are dressier but you just need to hit the bar at these place, order a beer and your tartare.
Seems everyone and their brother has a tuna tartare. Most over-done dish currently in America, but I love the stuff.
2927 Maple Avenue, Dallas, TX 75201
Dallas Chop House
1717 Main Street, Dallas, TX 75201