Cava

Cava Mezze Grill is a more recent Bethesda restaurant addition that does "upscale fast food" right. A Mediterranean cafeteria, Mezze allows you to customize your meal with fresh, interesting ingredients - it's the antithesis to McDonalds in every way except for speed.

You start with a base: pita, bowl, mini pitas, salad, to start building your sandwich/wrap/etc.
Next you can choose from their tasty dips and spreads: hummus, eggplant & red pepper, tzatziki, roasted red pepper hummus, and "crazy feta."
Then you select your protein: chicken, grilled meatballs, lamb, beef, or falafel (which I chose, and they were crispy, used with fresh chickpeas for that lovely hint of green and amazing texture.)
Then you add your toppings: tomato and onion/cucumber salad, cabbage, feta, kalamata olives, diced cucumbers, basmati rice, fresh mint, lemon, pickled onions, etc.
and dressing: yogurt dill, lemon herb tahini, spicy harissa, and Greek vinaigrette.
Warning: I got some harissa on my salad (with falafel, roasted red pepper dip, feta, and lemon herb, the bright pop of green on top) and it is extremely spicy. I've had harissa in Morocco, and knew what to expect, but if you're not big on spice then taste it with caution. It's intense. Awesome, but admittedly intense.

Cava is a bit pricier than other quick lunch options, certainly more than a dollar menu or sub chain, but you get the quality you pay for. The portions are massive, the veggies are crisp and the dips authentic, and even though it's a quick-order line, the interior of the cafe is very cozy if you do want to stay rather than take it to go. A great choice for lunch with friends. 3 stars.