Start your soaking in the morning because you will want to soak it for 24 hours, and the bake time is long. Starting your soak after breakfast will allow you to bake during the morning and afternoon and be done with it before dinner next day.
Combine your oats with the melted oil, melted butter and kefir (or buttermilk) in a very large bowl, add water last because you may not need much. Mix well. Cover with a cloth and let it sit at room temperature for 24 hours (keep it cooler, rather than warmer). After the soaking, preheat the oven to 200° F.
Combine the honey, maple syrup, salt, cinnamon and vanilla in a small pot of on the stove. Bring to a gentle simmer, stirring the mixture, until honey becomes thin.
Combine honey and oat mixtures, mix well.
Spread mixture out over parchment paper on cookie sheets, or just spray the pans lightly with cooking spray.
Bake for 4 hours, until granola is crunchy. It will seem slightly soft, but it crisps up as it cools. Turn the oven off and cool in the oven. Do not turn the oven up because you will burn your granola, and burnt granola is not tasty (ask me how I know!). Just cook it low and slow. Your patience will be rewarded for a good month or longer. I stir my granola every 30 minutes.
Mix in the coconut, seeds, dried fruit and nuts. Store in an airtight container in the refrigerator. On the counter for a few days or in cool weather is fine, but I have heard many people talk about their soaked granola molding in just a few weeks. Mine has never molded, but I have never kept it on the counter for more than a day - we always put it back in to chill.