chunky granola > pile of toasted oats

A little molasses adds great flavor and will help it clump up. Also, try adding 1-2Tbls chia seeds to your granola mixture before baking. These will become kind of gooey when exposed to or soaked in liquid--you can use it as an egg replacer in some recipes. Anyway, in granola it helps create more clumps and gives an added nutritional "multi-grain" aspect.

For that matter, my aunt's granola recipe uses egg in it. She took an oatmeal cookie recipe and granolified it. It's wonderfully clumpy!

You need a little fat (oil) and a little sweetener (brown sugar, maple syrup, honey, agave, etc.) to bind clumps. I try to use as little as possible because I don't like it to be very sweet. Also don't add the dried fruits until after granola is baked. Baking the fruits will both inhibit clumping and risk burning the fruits.

I make granola a couple times a month, and recently slightly adjusted my recipe after reading this article to get more clusters. I need to do a little more tweaking, but there was a difference after using more oat bran in my recipe (in lieu of going to the store for oat flour or quick oats).

Here's the link:
http://www.thekitchn.com/thekitchn/breakfast/cluster-granola-from-melissa-of-the-travelers-lunchbox-breakfast-with-a-blogger-141777

I make betteirene's granola all the time. It's really good! And has some nice chunks.

The sugar or sweetener in the granola, needs to undergo the process by which it becomes 'candified' (as in the 4 stages of soft ball, hard ball, soft crack, hard crack etc) at the same time as the oats get toasted, thus when the granolas is being made & the oats are getting nicely browned, the sugar / honey also heats up *& gets to a candy like state. as it cools, the candy incorporates the morsels of grain & nuts & hardens into clumps.
Go with Betteirenes recipe, she's explained the method very well. The honey & the brown sugar will melt, go thru the solidifying process by losing their moisture under the 300 F heat. the stirring in between will result in clumps & you'll have a granola to truly savor!

That sounds wonderful Izzbel I never thought of adding butter and coconut oil, Going to try this as I also like my granola chunky.

In my experience, the trick is to use something to bind the flakes together into clumps, just like sdebrango says. I make a super-chunky chewy granola using a very similar formula - a handful of whole wheat flour, some butter (and sometimes coconut oil), and lots of honey to bind everything together.
I also press it the granola into a hard-packed mound when I first turn it out onto a cookie sheet for baking, and then very gently break it up about halfway through. It comes out much clumpier than if I'd just spread it out into an even layer and not pressed.

Oh I forgot I also add sweetened flaked coconut it adds another layer of nuttiness.

The granola I make has nice clumps, use honey, canola oil to bind and sweeten and I like lots of nuts use pecans and walnuts and nut flour. The nut flour clumps with the oats, honey and oil. I mix with my hands scrunching it not over mixing that way it doesn't break down. The nut flour is not actual flour its ground nuts. I use either hazelnut or toasted almond, I order it from King Arthur but you can grind your own,

My mother uses honey, and has a moderate amount of clumps.

Sounds like you need to be sweetened up. Sugar is the glue that holds granola together so that it forms clumps. You could add a tad bit more of the sweetener called for in your recipe. When you bake it, stir it only as often as you need to so that it doesn't burn, and don't stir it thoroughly--just move it around a bit. Let it cool completely on the baking sheet before storing it, and handle it as little as possible after it has cooled--like, store it in a plastic container instead of in a zipper bag.

In a large bowl, stir together 1/2 cup honey, maple syrup or corn syrup, 3 tablespoons vegetable oil and 2 tablespoons brown sugar. Stir in 2 cups old-fashioned oatmeal (not quick-cooking and not steel-cut oatmeal), 1 cup of your favorite unsalted chopped nuts, 1/2 cup coconut, 1/4 cup wheat germ, 1/2 cup shelled, unsalted sunflower or pumpkin seeds. Spread onto a rimmed baking sheet lined with foil or parchment. Bake at 300 degrees for 30 minutes or until color changes to a light golden brown, stirring gently twice during this time. Cool completely before adding raisins, dried cranberries, chopped dates or other dried fruit.

I was researching how to make chewy bars like the ones quaker makes, and I know a lot of recipes had used corn syrup, but I bet there's a better solution! But that might work?