I ordered build-your-own bowls from Cava and Sweetgreen. Both tasted delicious, but the winner didn't charge for as many add-ons.

On a recent business trip to Chicago, I ate a lot of unhealthy food.

I attended a restaurant conference where I gorged on samples of vegan chicken, sushi, and brownies; I had a teriyaki burger and McPops at McDonald's Global Restaurant; I tried the massive portions at the Cheesecake Factory; and I sampled fine dining at a Michelin-starred restaurant.

I was urgently in need of some vegetables and grains to balance it out, so I headed to rival salad chains Sweetgreen and Cava to stock up on vitamins.

The Sweetgreen restaurant was light, airy, and almost deserted. I did arrive at nearly 8 p.m. on a Sunday, after all.

Sweetgreen sells bowls, salads, and protein plates.

A number of them were designed to be ordered as is, which started at $12.95, but you could also build your own in a walk-the-line format from $9.95. Mine ended up costing far more than this, though.

Five Guys stores say where that day's shipment of potatoes came from — but I was impressed to see a long list featuring many of Sweetgreen's suppliers. A lot of the ingredients were organic, too.

Sweetgreen has five leaf and three grain bases to choose from.

I started with a wild rice and herbed quinoa base — I liked that I could go 50/50 with them. There was a good choice of cold toppings, including different cheeses, nori sesame seasoning, spicy broccoli, crispy rice, and almonds.

There were hot toppings, too, including warm portobello mushrooms, roasted tofu, and caramelized garlic steak. It was a shame you couldn't get a better view of them, though.

Nearly half of Sweetgreen's toppings are listed as "premium" — meaning they incur extra charges.

The prices varied considerably at the restaurant I visited: it was $6.25 for steak, $5.95 for salmon, $2.10 for avocado, and $1.50 for blue cheese, goat's cheese, and shaved Parmesan. Keeping track of how much your meal will cost requires some quick maths.

I ended up going for what was, to be honest, quite an odd selection of toppings.

These included kale, pickled onions, warm portobello mushrooms, roasted tofu, avocado, tomatoes, and breadcrumbs. I had to pay extra for the mushrooms, tofu, and avocado.

My bowl made it a bit tricky to choose a dressing, though.

I wasn't sure what would go with the odd array of ingredients I'd chosen. Olive oil would have worked but would have been a bit boring. I asked the staff member for recommendations, and they suggested the Green Goddess Ranch.

They said that rather than pouring it on my salad, they could give it to me in a tub on the side.

I'm so glad they did.

I'm a Brit who's rarely eaten ranch — and I didn't know what made the ranch green. Turns out it was cilantro and parsley, two of my least favorite herbs. After a few tastes, I had to throw the tub away.

The bowl looked really attractive with its vibrantly-colored vegetables.

I thought it tasted delicious, though the mushroom wasn't as flavorsome as I'd expected and it was a shame about the dressing.

My portion of avocado wasn't sliced, which I found a bit impractical because all the other components were in bite-sized chunks.

The quinoa was really clumpy, too, but this was probably because I visited late in the evening. Maybe the batch had been standing around for a while.

My bowl came to $18.89 including tax and without a drink, which I thought was quite expensive, though it was a generous portion.

I went to Cava at a similar time of day — around 8 p.m., but this time, on a Friday.

Unlike the Sweetgreen I visited, the Cava was crammed full of customers. The restaurant — Chicago's first Cava — had only opened three weeks before, and residents of the Windy City were clearly eager to check out the buzz. It took me an hour to get to the front of the line.

Like Sweetgreen, Cava has a walk-the-line format and sales are dominated by custom dishes.

Customized grain bowls, salads, and pitas make up roughly 85% of Cava's orders. Prices for its most basic "curated" bowls start at $12.05, the same as a custom bowl with no paid-for add-ons.

Cava's menu is focused on Mediterranean ingredients.

You can get harissa honey chicken, braised lamb, Persian cucumber, spiced feta, and red pepper hummus. Dressings include balsamic date vinaigrette, tahini Caesar, and skhug — a spicy, herby sauce from Yemen.

Like at Sweetgreen, you have to pay extra for some of the toppings.

When I visited, three of the seven items described as "mains" — harissa honey chicken, braised lamb, and spicy lamb meatballs — incurred extra charges. Cava has now added grilled steak to this list, too.

But all the other toppings, apart from avocado, were free to add on.

This included vegetable slaw, hummus, and cheese, all of which incur extra charges at Sweetgreen. Falafel, roasted white sweet potato, grilled chicken, and roasted vegetables were free, too.

Cava has five leaf and three grain bases to choose from.

I went for Cava's SuperGreen mix topped with roasted white sweet potato, falafel, hummus, roasted eggplant dip, black olives, pickled pink onion, cabbage slaw, and garlic dressing. I also added Cava's pita crisps for free. My bowl looked monstrous, but it tasted great.

The white sweet potato wasn't as soft as I'd expected, and the pita chips soon became very soggy from the dressing, but other than that I loved my bowl.

As I didn't get any of the paid-for extras, I was just charged the base price of $12.05 before tax. With a drink, it came to $17.22, including tax.

I love eating at restaurants where you can build your own plate or bowl, eyeing up the tastiest ingredients as you go.

I can avoid ingredients I don't like, such as cilantro, parsley, and raw carrot — as well as the embarrassment of having to ask a member of staff if the restaurant could make a set menu item without these ingredients.

Both restaurants offered an extensive choice of ingredients — but Cava was the winner for me.

Though Sweetgreen offered a cheaper basic bowl — $9.95 versus $12.05 — many more of the toppings incur extra costs. I loved that Cava's falafel and sweet potato didn't cost more. If you made a bowl at Sweetgreen without any of the add-ons, it would be tasty but lacking some oomph.