hare krsna. If u would really like to offer something hot to your deities and have them as prasadam during the cold season, you may offer milk that has been boiled with a pinch of cardamom or alcohol-free vanilla extract. Such hot milk would be excellent. If you would like to have coffee, decaff coffee is also rejected as decaff coffee has been proven to be not 100% caffeine free. As such it would be unofferable to Krsna or any other deities. Most of our deities are visnu-tattva(incarnations of Krsna) as such they are only to be offered food items in the mode of goodness and that prasadam would also be suitable for us. Its nonsensical to say that we should have different levels of standard in following the rules n regulations. Cocoa is restricted in terms of offering to krsna n consuming according to srila Prabhupada's standard. This is simply due to the fact that caffeine is present in cocoa. A such we shud not drink hot chocolate or even eat chocolates for that case. However many Iskcon devotees still consume cocoa. Carob is a caffeine-free substitute for cocoa if u didnt know earlier. To make offerable naturally caffeine-free coffee, simply dry roast about 6 to 7 pieces of cloves for about a min in a heavy bottomed pan and then add 1 cup of corriander seeds and dry roast in medium flame till it becomes blackish and smokes a bit. To this add half cup sugar and allow the sugar to mix with the dry roasted ingredients and melt. once the sugar is melted and turns dark brown like caramel, add half cup of water and give a quick stir and then add 6 cups of milk or slightly more or less according to ur preffered strength. Bring milk to a boil and it would smell similar to milk coffee. once it boils and rises, switch off stove and filter the contents to get the hot beverage. you may reheat the drink after mixing the offering back to the main batch of preparation so that you can drink the prasadam "coffee" piping hot. hare krsna. hope this helped u to improve ur krsna consciousness.
ur servant
Vamsidhari Das