Many muffin, quick bread, etc., recipes call for things like juice rather than dairy and oil rather than butter.

You would have better success by searching for a good recipe using ingredients you want than by trying to alter all of the ingredients in an existing recipe.

Miyokos plant milk butter.

😉

I have cooked without dairy for over twenty years. My garandson cannot eat any dairy. It is not a problem.

I have to ask why you specified "fresh" dairy. I would think that you were talking about uncultured dairy as per that.

You could always use shortening in place of butter. Of course, not for butter cookies.

There is not always a sub for the original ingredient.

One thing about having dietary restrictions imposed upon you is that is can lead you to discover a different world of food and have some different expectations. And, that can be a good thing.

For myself, if I could not use butter, I would just not make butter cookies. And the same for other substitutes that people seek out. Instead of trying to make things imitate the orginal, just go for something completely different. NOT eating butter cookies is probably a good and positive thing.

Some people will take a dietary restriction and turn their diet around entirely and find an unexpected advantage comes to them as a result.

I use buttermilk in ALL of my baking, instead of sweet milk. Yes, of course, it is dairy, but is not "fresh" milk, since it is cultured. So, not sure what you mean by "fresh" dairy.

But it is clear that you are now avoiding ALL dairy. I would miss cheese the most. If I cant have the real thing, I dont want an imitation one. I would rather have none.

I mentioned butter cookies to highlight the limitations of vegan baking sticks. You'll get okay cookies if you use them but the difference will show. In the OP's quickbreads it'll be much less of a difference. It's never fun having your life upended. It takes awhile to make a total change comfortable. Vegan quickbreads are good. But the elimination diet may be over before the comfort with different ingredients sets in.

For only five weeks it shouldn't be too hard to do no baking at all and to use vegetable or animal fats in other cooking. If baking is a must there are plenty of cakes made with oil. I agree with those who suggest just avoiding rather than subbing. For the sake of a healthy diet baking is a special occasion activity in our house, not a regular thing, and it's fine. Cheese would be hard to go without, but, again, five weeks should be fairly easy.

As I said above it is no problem to go dairy free. I even have to go nut free also.

I like:

Earth Balance vegan margarine.

Silk soy milk, not the extra vanilla

Phillidelphia non dairy creme cheese

For cheddar cheese; Daiha "Melts like Dairy" or Violife

My grandson likes oatmilk. Coconut milk or cream is good for somethings, but it is sweet and does give a coconut flavor sometimes.

I make the Fantasty fudge at Christmas and we like it better than the milk version. I does take a bit longer to cook. I use soy milk for that.

I make my Dad's chocolate cake dairy free and my son made a pumpkin cake with cream cheese frosting last Thanksgiving that was great.

Cornbread is fine non dairy.

All vegetables are fine. Pancakes are fine.

All of the non dairy sourcream and etc. are great.

The only hard part was when we had to cook without eggs! That was "interesting". Thank goodness he out grew that. ( for reference, the plain gelatin worked for an egg substitute.)

ETA: I make whipped cream with the solids out of coconut milk. You cannot tell the difference.

Try cutting back on all animal fats and fried foods. A few years ago I was getting a slight upset stomach and nausea after eating. I had an endoscopy and was diagnosed with gastritis. One day, after a fatty meal, it was worse than usual and I made the connection to fats in my diet. I cut back on fats and seldom get those symptoms now, but if I do, Pepto Bismal is the only thing that settles my stomach.

I replace butter or oil with applesauce in a lot of cakes, muffins, quickbreads. Since it has binding properties, it can be partial in the egg replacement, but relying on it to be an egg replacement results in a denser cake- adding in a bit of levening can help with that. Sour cream can be subbed with silken tofu- add lemon juice, vinegar, and a bit of salt to taste. Blend it till creamy and smooth. The soft or firm level of the tofu will dictate how liquid or firm your sour cream ends up.