Method 1: Crafting Table
Place 3 Nether Bricks in a Crafting Table to make 6 Nether Brick Slabs.
6 How to Make a Nether Brick Slab in Minecraft
Use this simple recipe to make a Nether Brick Slab in Minecraft. You can see the exact ingredients, recipe layout, and workstation below.
Nether Brick Slab recipe
Follow the recipe below. The pattern must use the correct slots when the recipe is shaped.
6 
Method 2: Stonecutter
Use 1 Nether Bricks in a Stonecutter to make 2 Nether Brick Slabs.
2 About this Minecraft recipe
This page shows the vanilla recipe for Nether Brick Slab. It includes the exact ingredients, recipe layout, required workstation, and amount produced.
The data comes from Minecraft Java 26.2. Recipes can change in later game versions, so check the version you play before crafting.