I've eaten at the Grand Lux Cafe at the Venetian for lunch on my past two trips to Vegas. It's the perfect lunch spot! Prices are reasonable and portions are really big! It's owned by Cheesecake Factory so it gives you an idea of what to expect on the menu - tons of choices (minus the cheesecake).
Breakfast is offered until 11:00am but there is a separate breakfast menu if you want to order breakfast after 11:00am (limited menu).
I never realized how big the restaurant actually is and it seems very popular so it can get tough to get your server's attention. It took forever and a day for us to get our bread and other requests. The bread is REALLY fresh and yummy but it's served with hard butter (sigh) so I forgoed the butter.
For this past visit I tried the Santa Barbara Chicken Sandwich (grilled chicken breast, bacon, avocado, cheese, lettuce and tomato) with fries on the side. Both the sandwich and the fries were delicious! Generous portion of fresh avocado.
I'd come back. =)