We almost always use a good amount of seasoning in the food we serve. We try to skew towards fresh herbs and to spices that are not, well, too spicy. We take it easy on the salt and pepper, but use both. We use plenty of dried ginger, paprika, oregano, thyme, rosemary, basil, et al.

I think that garlic and cinnamon (not together, that might not taste so great) are good ones to start with.

I was shocked to discover (quite by accident!) that my son LOVED salsa- the hotter the better- as early as a year! I guess my Texas roots are manifesting themselves? He really likes salsa on his eggs and quesadillas. He also loves lemons and limes.

I am not sure what age you are asking about--for exs, I did follow a fairly strict 1 food at a time rule for the first month, to ensure they were not allergic to anything. So if that is what you mean, I am not sure and have no experience to offer. But after that, my kids ate EVERYTHING, except really hot stuff. My youngest's first meal at around 7-8 mos (first time I didnot do just 1 or 2 foods at a time I mean) was a pureed Afghani bean soup.

I completely agree with this theory--if you take a peek at my blog (shameless self promotion but truly relevant in this case) you will see I cook a very wide range of international cuisines and my kids eat them all (ages 3 and 4.5). The only one I have a wee bit of trouble with is Thai food because it can be hard to remove the heat, but even there they love the various fried noodles. And my youngest does not mind heat, but sadly so far for us my elder daughter does not like anything too hot.