Miranda Cosgrove's opening up about a scary experience with a stalker ... talking about a man who once lit himself on fire in her front yard -- and, she's still scared of the house because of it.

During an interview with Bustle, Miranda opened up about the man who stalked her about eight years ago ... before he ended up lighting himself on fire and shooting himself to death on her lawn.

She says this all happened right after he shot a woman who looked like the actress while she was driving outside her home ... and, the whole incident left Cosgrove traumatized.

Miranda told the outlet she wouldn't really stay in the house where the incident went down for two years following that ... and, she made regular trips back and forth to her parents' place just to feel safe.

She says she got into a relationship with someone who made her feel more comfortable there ... but, ultimately, she doesn't like going to the house alone.

Given her experiences ... Cosgrove says she finds Richard Gadd's "Baby Reindeer" show super inspiring -- saying she's not sure if she could confront her past trauma like he has.

Of course, Gadd's show's courted controversy recently ... with a woman claiming she's the real person behind the character Martha in the show -- and, saying it didn't go down as he claims.

In any case ... seems like Miranda's finally open to talking about the traumatic parts of her life -- a really big step, ya gotta say.