Fudge is sugary

What causes my fudge to turn sugary it tastes good but has a grainy texture

Cook the fudge to 240 degrees F. Once the fudge reaches soft-ball stage 240 degrees F (115 degrees C), do not stir it or even shake the pan until it has cooled to about 110 degrees F (43 degrees C). When pouring the fudge from the saucepan to the serving pan, don’t scrape the sides or bottom of saucepan or you may introduce unwanted sugar crystals into your finished fudge

Here’s a fudge recipe that is never sugary and is very smooth.

2 lb. sugar (4 cups)
1 cup regular milk
1 tsp vanilla
25 large marshmallows
1 cup butter
1 - 13oz Hershey bar
1 - 13 oz semi-sweet chocolate chips
2 oz Baker’s unsweetened chocolate
1 cup chopped nuts - optional

Mix sugar, milk, vanilla and butter in saucepan; bring to a boil and continue boiling for 2 minutes. (Stir while boiling-don’t burn it.) Remove pan from burner; add marshmallows - a few at a time until dissolved. Add chocolate, one at a time, and stir until it’s all melted. Pour into greased 11 x 15 x 1 in pan. Cool.

The sugar, milk etc mixture stays hot enough to melt all the chocolates. You don’t need a candy thermometer. Use a little butter to grease pan.