I just noticed that your recipe uses water. That's an ideal way to get tea flavor into things - you can replace it with concentrated tea. Assuming you use teabags, you should be able to steep two in that 2/3 cup of water. Tea is a fairly subtle flavor, so you may not taste it too much in the bread, but this is easy and doable with what you have! There's also instant tea, if you want to try to boost it - but it of course won't be as good as real, fresh tea. (You could buy chai concentrate, but I think it's usually about double strength, so not really better than you'll do on your own.)
I'd then replace the spices normally in your recipe with chai spices. If you've ever made chai from scratch, you could use that recipe as a guide, but it sounds like you might not have. There's an awful lot of variety here, from region to region, and in Western variations; you could search around online for chai recipes that appeal to you. I'm not an expert (I'm from Texas!) but from what I know, here are some common spices, with the most standard ones toward the top:
- cardamom
- cinnamon
- fresh ginger
- black pepper
- fennel
- cloves
Cardamom is pretty much required, and that'll help give you a flavor very different from your usual spice blend. I'd mix/grind up the spices separately from the rest, smell them to see if they're what you're looking for, and adjust as needed before mixing into the rest. Aiming for a similar total volume of spices to that of the original recipe should work fairly well. It might be a bit spicier, since you'll also have the tea, but that's probably fine. (Fresh ginger obviously won't go with the dry spices, if you use it - maybe a teaspoon or two minced?)
The way we make Chai in India ( there are lots of variants of the spice mix) is to use the spices whole while brewing the tea and to strain the tea before drinking.
Though for cardomom you should crush it to release the flavor. I would suggest using your hand or the broad side of your knife blade.
If you decide to use ginger, it might be a good idea to grate it to increase the surface area so that the flavor is absorbed quicker. (Ginger chai is really good in winter :))
Best Answer
Some powders mix better with cold water than hot, and milk powder seems to be one of them. Making a paste using a small amount of water also helps.
You can make a paste of cold water and milk powder in the cup before adding the tea, or you can make the paste, add the tea, optional sugar and more water, then boil. You may be able to put the powder in the cup, ad a small amount of tea and make a paste, then add the rest of the tea while stirring.
I do something similar with instant hot chocolate (which contains powdered milk) if making it in a mug. Another approach (which I use with instant hot chocolate when taking it out hiking) is to use a vacuum flask like a cocktail shaker: put the powder in and half fill with water, shake hard, then top up the water. Unless you want the tea in a flask this is just a way of making more washing up.
As an alternative, milk-based powdered whiteners sold for tea and coffee have more soluble ingredients than milk derivatives, and don't form clumps. The ingredient list for one I could easily buy is Glucose Syrup, Coconut Oil, Stabiliser (Dipotassium Phosphate, Sodium Polyphosphate), Milk Proteins, Emulsifier (Mono- and Di-Glycerides of Fatty Acids), Anti-caking Agent (Silicon Dioxide), Colour (Beta-Carotene). Other whiteners have no milk in them at all.