Mine is a Joe Wicks recipe.
For 8 portions: Mix together 140g oats, 85g pecans (broken up into small pieces), 85g mixed seeds, 85g unsweetened coconut flakes.
Seperately, melt 45g coconut oil and mix with 45g runnhy honey and around 100g unsweetened apple puree. For the latter you can mash up an apple, I guess you can probably buy unsweetened apple sauce, or you can use a pouch of unsweetened baby fruit puree (the easiest option!)
Mix the dry and wet ingredients together thoroughly. Spread out on a baking sheet. Bake at around 170 - 180c for around 20 mins. You'll need to stir it around during this time or it will burn at the edges and stay wet in the middle; you may also need to adjust the temp and timing according to your oven. I find it cooks v well in the airfryer; with that I cook it for ten minutes then 5 then another 5, with a good stir at each time break.
Serve with dried fruit - I mix together around 90g each of sultanas and chopped semi-dried apricots and divide that up. But if you mix these in with the cereal to store it, it goes soggy from the moisture in the fruit, so I keep the fruit in its own tupperware and add it when dishing up. I have mine with plain greek yogurt, or kefir, or an unsweetened fruit kefir yogurt.
ETA: As long as you cook this long enough (and at a temp that avoids it burning), it will be crunchy, and it will stay crunchy for a couple of weeks easily if it's in an airtight container. But you don't get big clusters with it.