Chung cake
It's also called "square cake". Chung cake is one of the traditional foods in my country. In the past, Vietnamese only made Chung cake on Tet holiday ( Lunar new year), but nowadays, when people don't have to can't make ends meet, you can buy it anywhere and anytime you want. A Chung cake includes sticky rice, green bean, meat pork, and onions, all of them are wrapped by in/with 4 green bamboo leafs leaves. It is boiled in for 8 to 12 hours. After it is cooked, they press it between 2 trays {with a heavy thing above} to make Chung cakes tight and be regular in shape. Square cake can keep 3-5 days without spoiling. It's so delicious. It's more delicious if you fry it and eat Chung cake with pork pie of or boiled chicken.For me, Tet holiday will would be ruined without Chung cake.
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don't have to = you have a choice. 'make ends meet' = that you don't have enough money for things like food. So 'don't have to' + 'make ends meet' can't go together.
{with a heavy thing above} - You already said the trays are heavy and being pressed so you don't actually need to describe it more. Really, 'pressed' means to push down on something.
If you want to say more about how they are made... you can try something like this.
After cooking, the cake is pressed firmly{with great force} between two heavy trays to make it tight and regular in shape.