But two entrees just seemed like too much food.
"So one of us said, 'Why don't we just split something?'" says Ihms, who lives in Dallas. "It just made sense not to stuff ourselves or leave so much food behind. Then it dawned on me what we were doing."
What they were doing was portion control, a buzzword in America's battle against obesity.
At home, you can plan how much to eat, put your food on a kitchen scale, save leftovers for the next meal.
But eating out in a supersized world presents a buffet of challenges.
"A typical restaurant portion might be two or three servings," says Jennifer Neily, a dietitian at the Cooper Clinic. "And that's before the rolls and the chips and all the other extras."
Those factors can make calorie-counting at a restaurant next to impossible.
Most fast-food chains now reveal their nutritional content, either in a pamphlet at the restaurant or on Web sites. You may not want to know what's in that Super Value Meal, but it's not hard to find out.
Moreover, they're served in specific portions, so the totals are easy to add up.
But head upscale on the food chain and that's no longer true. From all-you-can-eat buffets to endless pasta bowls to restaurants that give you lots of food for your money, there's no telling how much fat, cholesterol and calories you're piling up.
"When we were younger and got to go out for dinner, it was a real special occasion," says Lori Goodman, a Weight Watchers group leader in Dallas. "It was a special treat, so you didn't have to worry about it so much.
"But with our busy lifestyles now, it's a necessity to eat out a lot," she says. "So you need to make better choices."
Researchers have documented that portion sizes have ballooned at many restaurants as Americans' appetites grow along with their desire to feel that they're getting their money's worth.
And when presented more food, says Barbara Rolls, professor of nutritional science at Penn State University, we're likely to eat it.
"As a species, we're very bad at resisting temptation," says Rolls, whose studies have shown that larger portions lead to more consumption.
"Customers like this food, and we're so concerned about value that we can't be expected to leave it on the plate," Rolls says. "But we're in the midst of an obesity epidemic which is going to overwhelm our health-care system, and something needs to be done."
Nutrition advocates are pressing the restaurant industry to make nutritional information more available to customers and offer more options to eat less.
In the meantime, Rolls says, "If you eat out a lot, you really need to have defensive strategies."
Goodman's advice includes not arriving too hungry, previewing the menu to scout the best options, asking for healthier substitutions and getting every sauce and dressing on the side.
"You'll get a taste and you'll be amazed what you have left," she says. "It's just part of being more mindful, and it's absolutely something you have to practice."
But the hardest part may be downsizing the notion of what constitutes a serving.
Nutritionists recommend visualizing a meat portion as the size of a deck of cards, a starch portion as the size of your fist. Neily says you should look at your plate as having four quarters: one-fourth meat portion, one-fourth complex carbohydrate such as pasta or potato, and one-half vegetables.
If a big restaurant portion is on the way, the simplest solution is to split it. If you don't have a dining partner, Goodman says, have the waiter bring the to-go box with the meal.
"If you cut your food in half right away and put half in your box, you won't miss it," she says. "Out of sight, out of mind. But if it's still in front of you, you'll keep picking at it."
Weight Watchers tends to provide catchy phrases to reinforce good habits, and portion control is no exception.
If there's too much on your plate, Goodman says, "we say you can waste your food, or you can waist your food."
Ihms says she and her boyfriend regularly share restaurant meals, "and it's opened up all sorts of possibilities.
"Our goal wasn't to save money, but sometimes it works out that way," she says. "You can order an appetizer or dessert, or get something else on the side."
And when they're finished, Ihms says, "there's still almost always something left over. We'll say to each other, 'How can one person eat all this?'"