Well, my most is filled with typos, hope it's still clear. I understand how upset you are and you absolutely can and should stand up for yourself.
Be firm when you discuss with you DH. You are not asking him or suggesting to him. You are telling him. His reaction will tell you a lot. His mother may very likely come between you two for a while if he's not able to stand up to her, and I'm not sure he is since he's hiding at work when she visits.
Posters on this site often say they have no idea what happened between them and their DIL. Suddenly, with no warning, they were put on low contact and then cut off from their son and his family. I hope you post hits home with many of them. This is why. This type of behavior is the root cause. And here, many of these posters are defending her and telling you to suck it up. This is why!
Imagine if the tables were turned and you went to stay in her house for 10 days. You went to the guest room she had prepared, stripped the bed and remade it with sheets brought you brought. Then you sat her down and explained why your sheets are so much healthier and better than what she provided.
Imagine she then provided lunch for your family. You get up, and bring groceries into the house to make a "healthy and nutritious lunch "for everyone, explaining to her and FIL along the way why your food was better for everyone than the food she had prepared and was sitting on the table.
Imagine the reason you were visiting was to celebrate MIL and FIL 50th wedding anniversary. Every year MIL re-creates the top layer of their wedding cake, complete with bride and groom figurines on top. But this year, you announce you will be making the dessert to celebrate and you've decided to make cheesecake.
The heads on this board would EXPLODE with anger for the MIL. And they should, you would be terrible rude and entitled and an awful guest.
So take all of that into consideration.
Talk with your husband. Tell him how its going to be. This is his mother.
-Ideally he takes the next 4 days off work to spend with her OR she moves to a hotel, if not, then you and the kids need some "plans" so you can get out of the house and get a break.
She can go sightseeing
-It's a NO to her being involved in the birthday cake. No separate cake when she leaves (she learns NO lesson that way), no baking it together (she's not capable yet of sharing).
-Deal with the "gifts" after she leaves. But, still. Donate them, don't keep them. They will just build the resentment.
-Next visit she stays in a hotel
-Next visit DH is to never leave her alone with you, ever.
-Next visit is a loooonnnnggg way away
-If you get any pushback form DH at all, it's couples counseling for you both.
OP, explain to your DH that this moment is very important. If this continues then someday, somewhere down the road one of two things will happen - you will get divorced or your family will go no-contact with his mother.
OR he can step up, manage her and save the relationship. She needs to be managed.